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INTERNATIONAL ATOMIC WEIGHTS
FOR 1913*
= 16
Name.
Symbol.
Atomic
Weight.
Name.
Symbol.
Atomic
Weight.
Aluminium
Antimony
Al
Sb
27.1
120 2
Molybdenum. .<S. .
Neodymium ....
Mo
Nd
96.0
144 3
A
39 88
Neon
Ne
20 2
.lgUll. . ......
Arsenic . k^. ....
As
74.96
Nickel if, . .
Ni
58.68
Barium
Ba
137.37
Niton
Nt
222 4
Bismuth ^
Bi
208
Nitrogen
N
14.01
Boron
B
11.0
Osmium
Os
190.9
Bromine . .
Br
79 92
Oxygren . .
O
16 00
Cadmium ^
Cd
112 40
Palladium
Pd
106 7
Caesium
Cs
132 81
Phosphorus. . .
P
31.04
C&lcium
Ca
40 07
Platinum
Pt
195 2
Carbon
c
12 00
Potassium
rr
39.10
Cerium
Ce
140.25
Praseodymium. . .
Pr
140.6
Chlorine . . .
Cl
35.46
Radium
Ra
226.4
Chromium
Cr
52
Rhodium
Rh
102.9
Cobalt *<...
Co
58.97
Rubidium
Rb
85.45
C o lumb ium
Cb
93 5
Ruthenium ....
Ru
101.7
Coooer * / f.
Cu
63.57
Samarium
Sm
150.4
Dv
162 5
Scandium
Sc
44.1
Erbium
**j
Er
167 7
Selenium
Se
79.2
Eu
152
Silicon
Si
28 3
Fluorine
F
19
Silver */
Ag
107.88
Gadolinium
Gd '
157 3
Sodium
Na
23.00
Gallium
Ga
69.9
Strontium
Sr
87.63
Germanium
Ge
72.5
Sulphur
S
32.07
Glu cinum
Gl
9 1
Tantalum
Ta
181 5
Gold
Au
197.2
Tellurium
Te
127.5
Helium
He
3 99
Terbium
Tb
159 2
Ho
1 AQ X
Thallium
Tl
204.0
H
1 008
Thorium
Th
232 4
Indium
In
114 8
Thulium
Tm
168.5
Iodine
I
126 92
Tin
Sn
119.0
Iridium
Ir
193.1
Titanium
Ti
48.1
Fe
55 84
Tungsten
W
184
Krypton
Kr
82 92
Uranium
u
238.5
La
139
Vanadium '
v
51
Lead S
Pb
207 10
Xenon
Xe
130.2
Lithium
Li
6 Q4
Ytterbium
Yb
172.0
Lutecium
Lu
174.0
(Neoytterbium)
Magnesium.
Me 1
24 32
Yttrium
Yt
89.0
Manganese . .*^. .
A.g
Mn
54.93
Zinc K\ . . .
Zn
65.37
Mercury k . .
Hg
200.6
Zirconium
Zr
90.6
* Compiled by the International Committee on Atomic Weights con-
sisting of F. W. Clarke, W. Ostwald, T. E. Thorpe, and G. Urbain.
LIBRARY
I UNIVERSITY OF
\CALIFORNIA
METHODS
IN"
METALLURGICAL ANALYSIS
BY
CHARLES H. WHITE
Assistant Professor of Mining and Metallurgy in Harvard University
and in the Massachusetts Institute of Technology
1O6 ILLUSTRATIONS
NEW YORK
D. VAN NOSTRAND COMPANY
25 PARK PLACE
1915
! :
Copyright, 1915
BY
D. VAN NOSTRAND COMPANY
THE SCIENTIFIC PRESS
BROOKLYN. N. Y.
PREFACE
IN this volume are brought together those methods in
metallurgical analysis which, owing to their fitness, seem to have
been most generally adopted in American metallurgical lab-
oratories. The procedures are given for the sake of clearness
in as direct statement as possible, without regard to literary
style.
Explanatory notes have been introduced where they are
most needed by the beginner, but are so subdued as not to annoy
the experienced reader who may wish to omit them.
From several years' experience I find that students who
have had adequate preparation in qualitative analysis can take
up metallurgical analysis at once without having previously
taken a general course in quantitative analysis. For the benefit
of such students the various operations in both gravimetric and
volumetric analysis are . described in detail at the beginning of
the book, and the methods that such students would ordinarily
take up first are given in greater detail than those which are
usually assigned after considerable experience has been gained.
For more details than it is possible to give in a work of this
kind, the reader should consult the references given in the foot-
notes, and in the bibliography on page 335.
In addition to those whose names are mentioned hereafter
in these pages, I am indebted to my colleagues; Professor Albert
Sauveur for many helpful suggestions, especially for the im-
provement of the chapter on Iron and Steel, and Professor G.
S. Raymer for valuable criticism of the chapters on Sampling
iii
819524
iv PREFACE
and Fire Assaying. I have also received generous assistance
in collecting material and in preparing the illustrations from
Mr. W. S. Weeks, Instructor; and Messrs. F. C. Langenberg
and R. S. Cochran, Assistants, in the Harvard Mining School.
C. H. W.
HARVARD UNIVERSITY,
CAMBRIDGE, MASS.,
Jan. 2, 1915.
TABLE OF CONTENTS
PAGE
Definition of the Subject 1
Purposes for which Analyses are Made 1
Selection of Methods 1
Equipment of the Laboratory 5
Sampling Necessity of Correct Sampling 8
Classification of Materials 8
General Principles of Sampling 8
The Operations of Analysis Gravimetric 15
Weighing 15
Care and Use of the Balance 15
The Weights 16
The Operation of Weighing 16
Precautions in Weighing 18
Weighing for Analysis 18
Dissolving 18
Reagents 19
Precipitation 20
Filtration 21
Use of the Gooch Crucible 25
Washing Precipitates 26
Burning Precipitates 27
The Care of Platinum 29
To Clean Platinum 29
The Desiccator 30
Weighing Precipitates 30
Calculation of Results 31
Factor Weights 32
Volumetric Analysis 33
Volumetric Apparatus 33
Cleaning Solution 35
Titration 35
Standard Solutions 36
v
Vl TABLE OF CONTENTS
PAGE
Volumetric Analysis Normal Solutions 36
Empirical Standard Solutions 37
Preparation of an Empirica IStandard Solution 37
Standardizing Solutions 38
Correcting a Standard Solution 39
Factor Weights for Standard Solutions 40
Indicators 41
Colorimetry 42
Methods of Analysis in the Metallurgy of Iron and Steel 45
Methods for Ores 45
Sampling Iron-ore 45
Sampling Ore in Cars 45
Moisture Sample 47
Sampling a Cargo 47
Preparation of the Sample 48
Moisture 48
Hygroscopic Water 49
Combined Water 49
Loss on Ignition 50
Iron in Ores 50
Potassium Permanganate Method 50
Standardization of Permanganate Solution ; 51
Iron in Ferrous Ammonium Sulphate Gravimetric Method 52
Potassium Bichromate Method for Iron in Ore 62
Determination of Ferrous Iron 64
Free Metallic Iron 66
Silica in Ore 69
Sulphur in Ore 73
Phosphorus in Ore 75
Alumina in Ore 87
Manganese in Ore 88
Lime in Ore 96
Magnesia in Ore 97
Titanium in Ore 98
Analysis of Iron and Steel 103
Sampling 103
Detection of Segregations of Sulphur 104
Silicon in Iron and Steel 105
Silicon in Ferro-Silicon 107
Sulphur in Iron and Steel 108
TABLE OF CONTENTS vii
PAGE
Analysis of Iron and Steel Carbon in Iron and Steel 115
Phosphorus in Iron and Steel 129
Manganese in Iron and Steel 132
Manganese in Ferro-Manganese and Spiegel 133
Titanium in Iron and Steel 135
Nickel in Steel 137
Chromium and Vanadium in Steel 141
Tungsten in Steel 146
Molybdenum in Steel 148
Molybdenum in Molybdenum Powders 149
Copper in Steel 150
Nitrogen in Steel 151
Hydrogen in Steel 153
Oxygen in Steel 155
Analysis of Iron Slags 157
Analysis of Limestone 160
Methods of Analysis in the Metallurgy of Copper, Lead, etc 168
Copper in Ore 168
Lead in Ore 175
Zinc in Ore 178
Arsenic in Ore 180
Analysis of Copper Matte 184
Analysis of Chilled Blast Furnace Slags 188
Analysis of Reverberatory Slag 195
Analysis of Briquettes and Other Copper-bearing Products 196
Analysis of Copper Bullion 197
Analysis of Alloys * 210
Brass and Bronze 210
White Alloys Containing Tin, Lead, Copper, Phosphorus, and
Antimony 213
Alloy Containing Tin, Copper, Antimony, Lead, and Zinc 215
Bismuth in Alloys -. 218
Analysis of Copper Containing Lead, Antimony, Arsenic, Iron, Cobalt,
Nickel, when only a small Sample of the Material is Available 220
Methods of Analysis in the Production of the Precious Metals 224
Fire Assaying 224
Assay of Gold and Silver Ores ' 224
Assay of Bullion 235
Gold and Silver in Lead Bullion 241
Gold and Silver in Cyanide Solutions . , 242
viii TABLE OF CONTENTS
PAGE
Methods of Analysis in the Production of the Precious Metals Prepara-
tion of Pure Silver. 242
Preparation of Pure Gold 242
Testing Cyanide Solutions 243
Cyanogen in Commercial Cyanide 247
Weight of Ore in Slime 248
The Platinum Metals 249
Analysis of Fluxes 253
Analysis of Fuels 253
Coal 253
Proximate Analysis of Coal 254
Sulphur in Coal 256
Ultimate Analysis of Coal 259
Calorific Power of Coal 260
Petroleum 271
Fractional Distillation of Crude Petroleum 272
Sulphur in Petroleum 272
Calorific Power of Liquid Fuels 272
Water in Oil 273
Gas Analysis 273
Calorific Power of Gas 283
Analysis of Clay 286
Methods for the Determination of Some of the Minor Metals 290
Chromium 290
Nickel and Cobalt 290
Cadmium 292
Mercury 293
Tin 294
Tungsten 296
Vanadium 297
Uranium 298
Methods for the Determination of Some of the Rarer Metals 299
Lithium 299
Strontium 300
Barium 301
Columbium and Tantalum 301
Caesium ." 302
Germanium ; 302
Glucinum 303
Thallium. . . 303
TABLE OF CONTENTS ix
Methods for the Determination of Some of the Rarer Metals Cerium . . 304
Thorium 304
Yttrium 305
Zirconium 306
Testing Lubricating Oil 307
Examination of Boiler Water 308
Detection of the Metals 314
Tables 324
The Elements; their Atomic Weights, Melting-points, Boiling-points,
and Densities 324
Factors " 327
Table of Logarithms 328
Gas Table 330
Density Table for Hydrochloric Acid 332
Density Table for Sulphuric Acid 333
Density Table for Nitric Acid 334
General References 335
Index 339
Table of Atomic Weights Inside of front cover
Table of Equivalent Weights Inside of back cover
METALLURGICAL ANALYSIS
Definition. Metallurgical Analysis is the application of
analytical-chemical methods to the chemical problems of
metallurgy, including problems of valuation and utilization as
well as of production.
Purposes for which Analyses are Made. The analysis of any
metallurgical material or product is made for one or more of the
following reasons: (1) As a basis for the estimation of its com-
mercial value, (2) to determine its fitness or adaptability to a
certain use, or (3) as a guide in the operation of a process or in
determining the efficiency of a process or treatment.
Selection of Methods. It is obvious from the above classifica-
tion that analyses are made either for technical purposes or
for commercial purposes. For example, the slag from a blast
furnace is analyzed to determine if the furnace charge is correct.
In the open-hearth process of steel making, frequent determina-
tions of carbon are made that the heat may be terminated when
the carbon has been reduced to the desired point. These deter-
minations are for technical purposes, and, while accurate results
are desirable, the important requisite is, that the results be
obtained within a specified time, even if the highest degree of
accuracy must thereby be sacrificed; for it is of no special value
to the metallurgist to learn the composition of the slag after
the whole lot of ore has been charged into the furnace; nor can
the steel maker use the carbon determinations if they are not
given to him within a few minutes after the samples of molten
steel are taken from the furnace,
METALLURGICAL ANALYSIS
SELECTION OF METHODS
On the other hand, buyers and sellers of blister copper must
know very exactly the percentage of copper as well as the amounts
of the precious metals present, in order to fix a just price for the
bullion. In making determinations for commercial purposes,
PLAN
FIG. 2. Details of Equipment of a Working Table.
especially in cases where large sums of money are involved,
the most accurate methods known must be applied, and should
be carried out by the most skilled analysts.
The metallurgical chemist should ordinarily select, for any
particular determination, the method by which he can obtain
METALLURGICAL ANALYSIS
LABORATORY EQUIPMENT 5
the most accurate result in the time allowed; but in cases where
only approximations to a fair degree of accuracy are demanded,
methods will be selected that are less expensive in time and
materials; for the chemical department as well as the other
departments of a metallurgical establishment should have
regard for economy of labor and materials.
Equipment of the Laboratory. The laboratory should be
designed and constructed for the special purposes for which it
is to be used, and it is economy to consider the special fitness
of an apparatus and the possible efficiency attainable by its
use, as well as its initial cost.
Laboratories for schools and for general metallurgical
analysis should have the working tables fitted for the ordinary
chemical operations of solution, evaporation, filtration, and
washing of precipitates, titration, etc. At each table there
should be gas, water, compressed air, suction, a hood with air-
bath and hot-plate.
The hoods should be conveniently placed and well ventilated.
They are better made of glass and, if flues for an up-draft
interfere with the light, the hoods should be provided with a
down-draft with strong suction. Such hoods are easily kept
clean, they do not obstruct the light, and in their use there
is no danger of dust falling from the flue to spoil determina-
tions.
A satisfactory arrangement of these details is shown in Figs.
1, 2 arid 3.* In addition to the exhaust from the hoods, fresh
filtered air should be supplied to the laboratory by a plenum
fan. The room should be well lighted; for colorimetry, light
from north windows is best.
There should also be sample grinders, drills for sampling
metals, stirrers, shaking machines, centrifugal machines, and an
electric current should be available for operating these machines,
* See " The Equipment of a Laboratory for Metallurgical Chemistry
in a Technical School." Trans. Am. Inst. of Mining Engineers, 35, 117.
METALLURGICAL ANALYSIS
LABORATORY EQUIPMENT 7
and for heating combustion furnaces and for electrolysis. There
must also be provided the necessary balances, a still for pure
water, calorimeters, colorimeters, and other special appliances
that may be demanded.
The works-laboratory designed for much routine analysis
Skylight
fftt /// rifffi/iiff/rffiri!mffiif/f/rrrifiiiinii[ini//niii /
SECTION ON A B
FIG. 5. Section through the Laboratory Shown in Fig. 4.
may have tables or sections fitted with the necessary appliances
and reagents for carrying out these special operations or deter-
minations with the greatest facility. Figs. 4 and 5 are the plan
and section of such a laboratory, described by Edward Keller.*
* Trans. Amer. Inst. Mining Engineers, 36, 3
METALLURGICAL ANALYSIS
SAMPLING
Necessity of Correct Sampling. By chemical analysis it is
only the small portion of material that is weighed, dissolved,
and analyzed, whose composition is determined. If, however,
the small portion analyzed has been taken from a larger quan-
tity which is uniform throughout, then the portion analyzed
was a true sample and the analysis indicates the composition
of the whole. It follows that every determination to be
of any value in metallurgy must consist of two distinct and equally
important operations. They are sampling and chemical analysis.
The object in sampling is to separate from the whole body
of the material whose composition is desired, a small quantity
for analysis that shall have the same composition as the whole;
for it is obvious, that if the sample is not representative, the
most accurate chemical analysis cannot give the information
desired, that is, the true composition of the material in question.
The sampling of ore, or mineral in place, * is not usually carried
out by the chemist, but sampling for all other purposes for
which metallurgical analyses are made is done by him, or under
his direction, and should receive his careful consideration.
Classification of Materials. The method of sampling will
depend upon the nature of the material to be sampled. For
convenience in the study of sampling, metallurgical materials
may be divided into the following classes:
1. Fluids (a) Liquids water, oil, molten metals, slags, etc.
(6) Gases flue gas, producer gas, etc.
2. Tough or sectile materials metals, alloys, etc.
3. Brittle or frangible materials ores, fluxes, coal, brittle
metals, alloys, etc.
General Principles of Sampling. It is practically impossible
to take a theoretically perfect sample of ordinary metallurgical
* Those interested in this subject will consult " The Sampling and
Estimation of Ore in a Mine," T. A. Rickard.
SAMPLING 9
materials, and the degree of perfection to be attained is usually
determined by the value and uniformity of the material in
question; the more uniform the material, the simpler and cheaper
is the work of sampling; and the more uneven the mixture, the
more difficult and expensive is the operation. For example,
the smallest quantity of pure water that can be taken is a fair
sample of the whole, while on the other hand it is practically
impossible to take a satisfactory sample of a very " spotted "
gold-ore.
To sample a fluid it is only necessary to mix it thoroughly
and withdraw any convenient portion. The sampling of metals
and alloys after solidification is not so easily effected as when
molten on account of the segregation of impurities on cooling.
It is therefore necessary to take drillings from such materials in
a systematic way and mix them thoroughly before taking out
the final sample. See page 197 for the sampling of blister
copper.
The method of sampling fraymental materials like ore, coal,
and limestone will be given under the analysis of each, and gen-
eral principles only will be considered here. The first considera-
tion is the quantity to be taken for the original sample. This
will depend upon the value and uniformity of the material and
the size of the largest particles. As has been said already, if
the material is uniform in composition, only a small portion is
required, and this is true regardless of the size of the lumps
into which it is broken, but ores that break into lumps of great
variation in size, are usually uneven in composition; that is,
the large pieces are probably very different in composition
from the fine. If such an ore is all crushed to a fine powder
and thoroughly mixed, any small portion may be taken as a
correct sample, but if it is not so crushed and mixed, the por-
tion taken for the sample must be larger, and the quantity will
depend upon the size of the largest particles of the material.
In problems of sampling there are so many unknown quan-
10 METALLURGICAL ANALYSIS
titles, and these are subject to such great variation that a mathe-
matical treatment of the subject does not yield results of a very
practical nature.* The most reliable way to determine what
size of sample should be taken from an unknown ore is to sam-
ple a large lot of it in duplicate. For example, if the ore is to
be shoveled from one place to another, every fifth shovelful
can be put alternately into two receptacles, so that when the ore
is all transferred, each receptacle will contain duplicate sam-
ples, each a tenth of the ore. These samples are then properly
prepared and assayed. If the assays from the two samples are
not concordant, within the limits of error in assaying, the whole
lot is sampled in duplicate again, every fourth or third shovelful
being taken and put alternately into two receptacles as before,
and the two again assayed. In this, or in a similar way, by
hand or by mechanical sampler, the smallest lot that may be
taken for a sample of each of various grades of ores has been
determined in many mining districts. These results have been
brought together and tabulated in convenient form by Prof.
R. H. Richards, f In his table which is here reproduced, it will
be observed that in the left-hand column is given the quantity
of ore that must be taken in order to obtain a fair sample of
the several grades of ore, described at the top of succeeding
columns, when the largest particles have the diameters given in
these columns.
For example, the sample of rich ore (column 5), whose coarsest
particles measure 5 mm. in diameter, must contain 500 Ibs.,
but that quantity will be sufficient for a sample of low-grade
or uniform ore (column 2) which has its coarsest lumps as large
as 18 mm. Also the sample of a rich ore whose largest particle
* E. D. Peters, " Practice of Copper Smelting," 8. " Ore Sampling,"
S. A. Reed, School of Mines Quarterly 3, 253, also 6, 351. " The Theory
and Practice of Ore-sampling," D. W. Brunton, Trans. Amer. Inst. Mining
Engineers, 25, 826. " Principles of Ore-sampling," A. Van Zwaluwenburg,
Mines and Methods, Oct., 1909.
t" Ore Dressing," 2, 852.
SAMPLING
11
Weight to be Taken
as Sample.
Diameter of the Largest Particle.
Grams.
Pounds.
Very
Low-
grade or
very
Uniform
Ores.
Low-
Srade or
niform
Ores.
Medium
Ores.
Medium
Ores.
Rich or
"Spotted"
Ores.
Very Rich
or Exces-
sively
"Spotted"
Ores.
1
2
3
4
5
6
mm.
mm.
mm.
mm.
mm.
mm.
20,000
207
114
76.2
50.8
31.6
5.4
10,000
147
80.3
53.9
35.9
22.4
3.8
5,000
104
56.8
38.1
25.4
15.8
2.7
2,000
65.6
35.9
24.1
16.1
10.0
1.7
1,000
46.4
25.4
17.0
11.4
7.1
1.2
500
32.8
18.0
12.0
8.0
5.0
0.85
200
20.7
11.4
7.6
5.1
3.2
0.54
100
14.7
8.0
5.4
3.6
2.2
0.38
50
10.4
5.7
3.8
2.5
1.3
0.27
20
6.6
3.6
2.4
1.6
1.0
0.17
10
4.6
2.5
1.7
1.1
0.71
0.12
5
3.3
1.8
1.2
0.80
0.50
2
2.1
1.1
0.76
0.51
0.32
1
1.5
0.80
0.54
0.36
0.22
0.5
1.0
0.57
0.38
0.25
0.16
90
0.2
0.66
0.36
0.24
0.16
0.10
45
0.1
0.46
0.25
0.17
0.11
22.5
0.05
0.33
0.18
0.12
9
0.02
0.21
0.11
4.5
0.01
0.15
2.25
0.005
0.10
,
measures 1 mm. in diameter must contain 20 Ibs., while that of
a very low-grade ore of the same size particle, would have to
contain only 0.5 Ib. This table shows not only how much should
be taken for the original sample, but also how much must be taken
from the original sample after it has been crushed finer and mixed,
so that the portion taken will still be a representative portion
of the whole.
After the sample has been taken either by hand or by a
mechanical sampler (Fig. 6), it is successively crushed and
12
METALLURGICAL ANALYSIS
FIG. 6. Vezin Sampler. This sampler cuts out at regular intervals a
section across the stream of crushed ore and is set to take a definite
fraction of the ore that passes through it.
''^Vi
fb
FIG. 7.
FIG. 8.
FIG. 9.
FIG. 7. The Sample is Shoveled into a Conical Heap on the Sampling
Floor. Each shovelful is dropped directly on the apex of the cone
so that the ore will roll down evenly on all sides of the cone.
FIG. 8. The Cone is Flattened by Drawing the Ore from the Center Out-
ward with the Shovel as the Sampler Walks around the Cone. The
cone is then quartered and opposite quarters are discarded.
FIG. 9. Split Shovel for Dividing the Sample.
SAMPLING
13
mixed and reduced in size in accordance with the table by
coning and quartering (Fig. 7, 8), by the split shovel (Fig. 9),
FIG. 10. Riffle for Dividing a
Crushed Sample into Halves.
FIG. 11. Riffle to be Placed on
Rubber Cloth when Used.
FIG. 12. Crusher. Sectional View.
or by riffles (Fig. 10, 11), until the quantity has been reduced
to a few ounces (Fig. 12, 13, 13a, 14), all of which will pass
through a hundred-mesh sieve; and with certain ores iron
14
METALLURGICAL ANALYSIS
FIG. 13. Pulverizer.
FIG. 13a. Bucking Plate and Muller
for Fine Grinding by Hand.
FIG. 14. Ball Mill for Soft Ore,
Coal, etc.
FIG. 15. Mechanical Grinder with
Agate Mortar and Pestle.
THE OPERATIONS OF ANALYSIS 15
ores for instance much time may be saved in dissolving the
ore if it is ground still finer in an agate mortar. Good mechanical
FOR 1913*
= 16
Name.
Symbol.
Atomic
Weight.
Name.
Symbol.
Atomic
Weight.
Aluminium
Antimony
Al
Sb
27.1
120 2
Molybdenum. .<S. .
Neodymium ....
Mo
Nd
96.0
144 3
A
39 88
Neon
Ne
20 2
.lgUll. . ......
Arsenic . k^. ....
As
74.96
Nickel if, . .
Ni
58.68
Barium
Ba
137.37
Niton
Nt
222 4
Bismuth ^
Bi
208
Nitrogen
N
14.01
Boron
B
11.0
Osmium
Os
190.9
Bromine . .
Br
79 92
Oxygren . .
O
16 00
Cadmium ^
Cd
112 40
Palladium
Pd
106 7
Caesium
Cs
132 81
Phosphorus. . .
P
31.04
C&lcium
Ca
40 07
Platinum
Pt
195 2
Carbon
c
12 00
Potassium
rr
39.10
Cerium
Ce
140.25
Praseodymium. . .
Pr
140.6
Chlorine . . .
Cl
35.46
Radium
Ra
226.4
Chromium
Cr
52
Rhodium
Rh
102.9
Cobalt *<...
Co
58.97
Rubidium
Rb
85.45
C o lumb ium
Cb
93 5
Ruthenium ....
Ru
101.7
Coooer * / f.
Cu
63.57
Samarium
Sm
150.4
Dv
162 5
Scandium
Sc
44.1
Erbium
**j
Er
167 7
Selenium
Se
79.2
Eu
152
Silicon
Si
28 3
Fluorine
F
19
Silver */
Ag
107.88
Gadolinium
Gd '
157 3
Sodium
Na
23.00
Gallium
Ga
69.9
Strontium
Sr
87.63
Germanium
Ge
72.5
Sulphur
S
32.07
Glu cinum
Gl
9 1
Tantalum
Ta
181 5
Gold
Au
197.2
Tellurium
Te
127.5
Helium
He
3 99
Terbium
Tb
159 2
Ho
1 AQ X
Thallium
Tl
204.0
H
1 008
Thorium
Th
232 4
Indium
In
114 8
Thulium
Tm
168.5
Iodine
I
126 92
Tin
Sn
119.0
Iridium
Ir
193.1
Titanium
Ti
48.1
Fe
55 84
Tungsten
W
184
Krypton
Kr
82 92
Uranium
u
238.5
La
139
Vanadium '
v
51
Lead S
Pb
207 10
Xenon
Xe
130.2
Lithium
Li
6 Q4
Ytterbium
Yb
172.0
Lutecium
Lu
174.0
(Neoytterbium)
Magnesium.
Me 1
24 32
Yttrium
Yt
89.0
Manganese . .*^. .
A.g
Mn
54.93
Zinc K\ . . .
Zn
65.37
Mercury k . .
Hg
200.6
Zirconium
Zr
90.6
* Compiled by the International Committee on Atomic Weights con-
sisting of F. W. Clarke, W. Ostwald, T. E. Thorpe, and G. Urbain.
LIBRARY
I UNIVERSITY OF
\CALIFORNIA
METHODS
IN"
METALLURGICAL ANALYSIS
BY
CHARLES H. WHITE
Assistant Professor of Mining and Metallurgy in Harvard University
and in the Massachusetts Institute of Technology
1O6 ILLUSTRATIONS
NEW YORK
D. VAN NOSTRAND COMPANY
25 PARK PLACE
1915
! :
Copyright, 1915
BY
D. VAN NOSTRAND COMPANY
THE SCIENTIFIC PRESS
BROOKLYN. N. Y.
PREFACE
IN this volume are brought together those methods in
metallurgical analysis which, owing to their fitness, seem to have
been most generally adopted in American metallurgical lab-
oratories. The procedures are given for the sake of clearness
in as direct statement as possible, without regard to literary
style.
Explanatory notes have been introduced where they are
most needed by the beginner, but are so subdued as not to annoy
the experienced reader who may wish to omit them.
From several years' experience I find that students who
have had adequate preparation in qualitative analysis can take
up metallurgical analysis at once without having previously
taken a general course in quantitative analysis. For the benefit
of such students the various operations in both gravimetric and
volumetric analysis are . described in detail at the beginning of
the book, and the methods that such students would ordinarily
take up first are given in greater detail than those which are
usually assigned after considerable experience has been gained.
For more details than it is possible to give in a work of this
kind, the reader should consult the references given in the foot-
notes, and in the bibliography on page 335.
In addition to those whose names are mentioned hereafter
in these pages, I am indebted to my colleagues; Professor Albert
Sauveur for many helpful suggestions, especially for the im-
provement of the chapter on Iron and Steel, and Professor G.
S. Raymer for valuable criticism of the chapters on Sampling
iii
819524
iv PREFACE
and Fire Assaying. I have also received generous assistance
in collecting material and in preparing the illustrations from
Mr. W. S. Weeks, Instructor; and Messrs. F. C. Langenberg
and R. S. Cochran, Assistants, in the Harvard Mining School.
C. H. W.
HARVARD UNIVERSITY,
CAMBRIDGE, MASS.,
Jan. 2, 1915.
TABLE OF CONTENTS
PAGE
Definition of the Subject 1
Purposes for which Analyses are Made 1
Selection of Methods 1
Equipment of the Laboratory 5
Sampling Necessity of Correct Sampling 8
Classification of Materials 8
General Principles of Sampling 8
The Operations of Analysis Gravimetric 15
Weighing 15
Care and Use of the Balance 15
The Weights 16
The Operation of Weighing 16
Precautions in Weighing 18
Weighing for Analysis 18
Dissolving 18
Reagents 19
Precipitation 20
Filtration 21
Use of the Gooch Crucible 25
Washing Precipitates 26
Burning Precipitates 27
The Care of Platinum 29
To Clean Platinum 29
The Desiccator 30
Weighing Precipitates 30
Calculation of Results 31
Factor Weights 32
Volumetric Analysis 33
Volumetric Apparatus 33
Cleaning Solution 35
Titration 35
Standard Solutions 36
v
Vl TABLE OF CONTENTS
PAGE
Volumetric Analysis Normal Solutions 36
Empirical Standard Solutions 37
Preparation of an Empirica IStandard Solution 37
Standardizing Solutions 38
Correcting a Standard Solution 39
Factor Weights for Standard Solutions 40
Indicators 41
Colorimetry 42
Methods of Analysis in the Metallurgy of Iron and Steel 45
Methods for Ores 45
Sampling Iron-ore 45
Sampling Ore in Cars 45
Moisture Sample 47
Sampling a Cargo 47
Preparation of the Sample 48
Moisture 48
Hygroscopic Water 49
Combined Water 49
Loss on Ignition 50
Iron in Ores 50
Potassium Permanganate Method 50
Standardization of Permanganate Solution ; 51
Iron in Ferrous Ammonium Sulphate Gravimetric Method 52
Potassium Bichromate Method for Iron in Ore 62
Determination of Ferrous Iron 64
Free Metallic Iron 66
Silica in Ore 69
Sulphur in Ore 73
Phosphorus in Ore 75
Alumina in Ore 87
Manganese in Ore 88
Lime in Ore 96
Magnesia in Ore 97
Titanium in Ore 98
Analysis of Iron and Steel 103
Sampling 103
Detection of Segregations of Sulphur 104
Silicon in Iron and Steel 105
Silicon in Ferro-Silicon 107
Sulphur in Iron and Steel 108
TABLE OF CONTENTS vii
PAGE
Analysis of Iron and Steel Carbon in Iron and Steel 115
Phosphorus in Iron and Steel 129
Manganese in Iron and Steel 132
Manganese in Ferro-Manganese and Spiegel 133
Titanium in Iron and Steel 135
Nickel in Steel 137
Chromium and Vanadium in Steel 141
Tungsten in Steel 146
Molybdenum in Steel 148
Molybdenum in Molybdenum Powders 149
Copper in Steel 150
Nitrogen in Steel 151
Hydrogen in Steel 153
Oxygen in Steel 155
Analysis of Iron Slags 157
Analysis of Limestone 160
Methods of Analysis in the Metallurgy of Copper, Lead, etc 168
Copper in Ore 168
Lead in Ore 175
Zinc in Ore 178
Arsenic in Ore 180
Analysis of Copper Matte 184
Analysis of Chilled Blast Furnace Slags 188
Analysis of Reverberatory Slag 195
Analysis of Briquettes and Other Copper-bearing Products 196
Analysis of Copper Bullion 197
Analysis of Alloys * 210
Brass and Bronze 210
White Alloys Containing Tin, Lead, Copper, Phosphorus, and
Antimony 213
Alloy Containing Tin, Copper, Antimony, Lead, and Zinc 215
Bismuth in Alloys -. 218
Analysis of Copper Containing Lead, Antimony, Arsenic, Iron, Cobalt,
Nickel, when only a small Sample of the Material is Available 220
Methods of Analysis in the Production of the Precious Metals 224
Fire Assaying 224
Assay of Gold and Silver Ores ' 224
Assay of Bullion 235
Gold and Silver in Lead Bullion 241
Gold and Silver in Cyanide Solutions . , 242
viii TABLE OF CONTENTS
PAGE
Methods of Analysis in the Production of the Precious Metals Prepara-
tion of Pure Silver. 242
Preparation of Pure Gold 242
Testing Cyanide Solutions 243
Cyanogen in Commercial Cyanide 247
Weight of Ore in Slime 248
The Platinum Metals 249
Analysis of Fluxes 253
Analysis of Fuels 253
Coal 253
Proximate Analysis of Coal 254
Sulphur in Coal 256
Ultimate Analysis of Coal 259
Calorific Power of Coal 260
Petroleum 271
Fractional Distillation of Crude Petroleum 272
Sulphur in Petroleum 272
Calorific Power of Liquid Fuels 272
Water in Oil 273
Gas Analysis 273
Calorific Power of Gas 283
Analysis of Clay 286
Methods for the Determination of Some of the Minor Metals 290
Chromium 290
Nickel and Cobalt 290
Cadmium 292
Mercury 293
Tin 294
Tungsten 296
Vanadium 297
Uranium 298
Methods for the Determination of Some of the Rarer Metals 299
Lithium 299
Strontium 300
Barium 301
Columbium and Tantalum 301
Caesium ." 302
Germanium ; 302
Glucinum 303
Thallium. . . 303
TABLE OF CONTENTS ix
Methods for the Determination of Some of the Rarer Metals Cerium . . 304
Thorium 304
Yttrium 305
Zirconium 306
Testing Lubricating Oil 307
Examination of Boiler Water 308
Detection of the Metals 314
Tables 324
The Elements; their Atomic Weights, Melting-points, Boiling-points,
and Densities 324
Factors " 327
Table of Logarithms 328
Gas Table 330
Density Table for Hydrochloric Acid 332
Density Table for Sulphuric Acid 333
Density Table for Nitric Acid 334
General References 335
Index 339
Table of Atomic Weights Inside of front cover
Table of Equivalent Weights Inside of back cover
METALLURGICAL ANALYSIS
Definition. Metallurgical Analysis is the application of
analytical-chemical methods to the chemical problems of
metallurgy, including problems of valuation and utilization as
well as of production.
Purposes for which Analyses are Made. The analysis of any
metallurgical material or product is made for one or more of the
following reasons: (1) As a basis for the estimation of its com-
mercial value, (2) to determine its fitness or adaptability to a
certain use, or (3) as a guide in the operation of a process or in
determining the efficiency of a process or treatment.
Selection of Methods. It is obvious from the above classifica-
tion that analyses are made either for technical purposes or
for commercial purposes. For example, the slag from a blast
furnace is analyzed to determine if the furnace charge is correct.
In the open-hearth process of steel making, frequent determina-
tions of carbon are made that the heat may be terminated when
the carbon has been reduced to the desired point. These deter-
minations are for technical purposes, and, while accurate results
are desirable, the important requisite is, that the results be
obtained within a specified time, even if the highest degree of
accuracy must thereby be sacrificed; for it is of no special value
to the metallurgist to learn the composition of the slag after
the whole lot of ore has been charged into the furnace; nor can
the steel maker use the carbon determinations if they are not
given to him within a few minutes after the samples of molten
steel are taken from the furnace,
METALLURGICAL ANALYSIS
SELECTION OF METHODS
On the other hand, buyers and sellers of blister copper must
know very exactly the percentage of copper as well as the amounts
of the precious metals present, in order to fix a just price for the
bullion. In making determinations for commercial purposes,
PLAN
FIG. 2. Details of Equipment of a Working Table.
especially in cases where large sums of money are involved,
the most accurate methods known must be applied, and should
be carried out by the most skilled analysts.
The metallurgical chemist should ordinarily select, for any
particular determination, the method by which he can obtain
METALLURGICAL ANALYSIS
LABORATORY EQUIPMENT 5
the most accurate result in the time allowed; but in cases where
only approximations to a fair degree of accuracy are demanded,
methods will be selected that are less expensive in time and
materials; for the chemical department as well as the other
departments of a metallurgical establishment should have
regard for economy of labor and materials.
Equipment of the Laboratory. The laboratory should be
designed and constructed for the special purposes for which it
is to be used, and it is economy to consider the special fitness
of an apparatus and the possible efficiency attainable by its
use, as well as its initial cost.
Laboratories for schools and for general metallurgical
analysis should have the working tables fitted for the ordinary
chemical operations of solution, evaporation, filtration, and
washing of precipitates, titration, etc. At each table there
should be gas, water, compressed air, suction, a hood with air-
bath and hot-plate.
The hoods should be conveniently placed and well ventilated.
They are better made of glass and, if flues for an up-draft
interfere with the light, the hoods should be provided with a
down-draft with strong suction. Such hoods are easily kept
clean, they do not obstruct the light, and in their use there
is no danger of dust falling from the flue to spoil determina-
tions.
A satisfactory arrangement of these details is shown in Figs.
1, 2 arid 3.* In addition to the exhaust from the hoods, fresh
filtered air should be supplied to the laboratory by a plenum
fan. The room should be well lighted; for colorimetry, light
from north windows is best.
There should also be sample grinders, drills for sampling
metals, stirrers, shaking machines, centrifugal machines, and an
electric current should be available for operating these machines,
* See " The Equipment of a Laboratory for Metallurgical Chemistry
in a Technical School." Trans. Am. Inst. of Mining Engineers, 35, 117.
METALLURGICAL ANALYSIS
LABORATORY EQUIPMENT 7
and for heating combustion furnaces and for electrolysis. There
must also be provided the necessary balances, a still for pure
water, calorimeters, colorimeters, and other special appliances
that may be demanded.
The works-laboratory designed for much routine analysis
Skylight
fftt /// rifffi/iiff/rffiri!mffiif/f/rrrifiiiinii[ini//niii /
SECTION ON A B
FIG. 5. Section through the Laboratory Shown in Fig. 4.
may have tables or sections fitted with the necessary appliances
and reagents for carrying out these special operations or deter-
minations with the greatest facility. Figs. 4 and 5 are the plan
and section of such a laboratory, described by Edward Keller.*
* Trans. Amer. Inst. Mining Engineers, 36, 3
METALLURGICAL ANALYSIS
SAMPLING
Necessity of Correct Sampling. By chemical analysis it is
only the small portion of material that is weighed, dissolved,
and analyzed, whose composition is determined. If, however,
the small portion analyzed has been taken from a larger quan-
tity which is uniform throughout, then the portion analyzed
was a true sample and the analysis indicates the composition
of the whole. It follows that every determination to be
of any value in metallurgy must consist of two distinct and equally
important operations. They are sampling and chemical analysis.
The object in sampling is to separate from the whole body
of the material whose composition is desired, a small quantity
for analysis that shall have the same composition as the whole;
for it is obvious, that if the sample is not representative, the
most accurate chemical analysis cannot give the information
desired, that is, the true composition of the material in question.
The sampling of ore, or mineral in place, * is not usually carried
out by the chemist, but sampling for all other purposes for
which metallurgical analyses are made is done by him, or under
his direction, and should receive his careful consideration.
Classification of Materials. The method of sampling will
depend upon the nature of the material to be sampled. For
convenience in the study of sampling, metallurgical materials
may be divided into the following classes:
1. Fluids (a) Liquids water, oil, molten metals, slags, etc.
(6) Gases flue gas, producer gas, etc.
2. Tough or sectile materials metals, alloys, etc.
3. Brittle or frangible materials ores, fluxes, coal, brittle
metals, alloys, etc.
General Principles of Sampling. It is practically impossible
to take a theoretically perfect sample of ordinary metallurgical
* Those interested in this subject will consult " The Sampling and
Estimation of Ore in a Mine," T. A. Rickard.
SAMPLING 9
materials, and the degree of perfection to be attained is usually
determined by the value and uniformity of the material in
question; the more uniform the material, the simpler and cheaper
is the work of sampling; and the more uneven the mixture, the
more difficult and expensive is the operation. For example,
the smallest quantity of pure water that can be taken is a fair
sample of the whole, while on the other hand it is practically
impossible to take a satisfactory sample of a very " spotted "
gold-ore.
To sample a fluid it is only necessary to mix it thoroughly
and withdraw any convenient portion. The sampling of metals
and alloys after solidification is not so easily effected as when
molten on account of the segregation of impurities on cooling.
It is therefore necessary to take drillings from such materials in
a systematic way and mix them thoroughly before taking out
the final sample. See page 197 for the sampling of blister
copper.
The method of sampling fraymental materials like ore, coal,
and limestone will be given under the analysis of each, and gen-
eral principles only will be considered here. The first considera-
tion is the quantity to be taken for the original sample. This
will depend upon the value and uniformity of the material and
the size of the largest particles. As has been said already, if
the material is uniform in composition, only a small portion is
required, and this is true regardless of the size of the lumps
into which it is broken, but ores that break into lumps of great
variation in size, are usually uneven in composition; that is,
the large pieces are probably very different in composition
from the fine. If such an ore is all crushed to a fine powder
and thoroughly mixed, any small portion may be taken as a
correct sample, but if it is not so crushed and mixed, the por-
tion taken for the sample must be larger, and the quantity will
depend upon the size of the largest particles of the material.
In problems of sampling there are so many unknown quan-
10 METALLURGICAL ANALYSIS
titles, and these are subject to such great variation that a mathe-
matical treatment of the subject does not yield results of a very
practical nature.* The most reliable way to determine what
size of sample should be taken from an unknown ore is to sam-
ple a large lot of it in duplicate. For example, if the ore is to
be shoveled from one place to another, every fifth shovelful
can be put alternately into two receptacles, so that when the ore
is all transferred, each receptacle will contain duplicate sam-
ples, each a tenth of the ore. These samples are then properly
prepared and assayed. If the assays from the two samples are
not concordant, within the limits of error in assaying, the whole
lot is sampled in duplicate again, every fourth or third shovelful
being taken and put alternately into two receptacles as before,
and the two again assayed. In this, or in a similar way, by
hand or by mechanical sampler, the smallest lot that may be
taken for a sample of each of various grades of ores has been
determined in many mining districts. These results have been
brought together and tabulated in convenient form by Prof.
R. H. Richards, f In his table which is here reproduced, it will
be observed that in the left-hand column is given the quantity
of ore that must be taken in order to obtain a fair sample of
the several grades of ore, described at the top of succeeding
columns, when the largest particles have the diameters given in
these columns.
For example, the sample of rich ore (column 5), whose coarsest
particles measure 5 mm. in diameter, must contain 500 Ibs.,
but that quantity will be sufficient for a sample of low-grade
or uniform ore (column 2) which has its coarsest lumps as large
as 18 mm. Also the sample of a rich ore whose largest particle
* E. D. Peters, " Practice of Copper Smelting," 8. " Ore Sampling,"
S. A. Reed, School of Mines Quarterly 3, 253, also 6, 351. " The Theory
and Practice of Ore-sampling," D. W. Brunton, Trans. Amer. Inst. Mining
Engineers, 25, 826. " Principles of Ore-sampling," A. Van Zwaluwenburg,
Mines and Methods, Oct., 1909.
t" Ore Dressing," 2, 852.
SAMPLING
11
Weight to be Taken
as Sample.
Diameter of the Largest Particle.
Grams.
Pounds.
Very
Low-
grade or
very
Uniform
Ores.
Low-
Srade or
niform
Ores.
Medium
Ores.
Medium
Ores.
Rich or
"Spotted"
Ores.
Very Rich
or Exces-
sively
"Spotted"
Ores.
1
2
3
4
5
6
mm.
mm.
mm.
mm.
mm.
mm.
20,000
207
114
76.2
50.8
31.6
5.4
10,000
147
80.3
53.9
35.9
22.4
3.8
5,000
104
56.8
38.1
25.4
15.8
2.7
2,000
65.6
35.9
24.1
16.1
10.0
1.7
1,000
46.4
25.4
17.0
11.4
7.1
1.2
500
32.8
18.0
12.0
8.0
5.0
0.85
200
20.7
11.4
7.6
5.1
3.2
0.54
100
14.7
8.0
5.4
3.6
2.2
0.38
50
10.4
5.7
3.8
2.5
1.3
0.27
20
6.6
3.6
2.4
1.6
1.0
0.17
10
4.6
2.5
1.7
1.1
0.71
0.12
5
3.3
1.8
1.2
0.80
0.50
2
2.1
1.1
0.76
0.51
0.32
1
1.5
0.80
0.54
0.36
0.22
0.5
1.0
0.57
0.38
0.25
0.16
90
0.2
0.66
0.36
0.24
0.16
0.10
45
0.1
0.46
0.25
0.17
0.11
22.5
0.05
0.33
0.18
0.12
9
0.02
0.21
0.11
4.5
0.01
0.15
2.25
0.005
0.10
,
measures 1 mm. in diameter must contain 20 Ibs., while that of
a very low-grade ore of the same size particle, would have to
contain only 0.5 Ib. This table shows not only how much should
be taken for the original sample, but also how much must be taken
from the original sample after it has been crushed finer and mixed,
so that the portion taken will still be a representative portion
of the whole.
After the sample has been taken either by hand or by a
mechanical sampler (Fig. 6), it is successively crushed and
12
METALLURGICAL ANALYSIS
FIG. 6. Vezin Sampler. This sampler cuts out at regular intervals a
section across the stream of crushed ore and is set to take a definite
fraction of the ore that passes through it.
''^Vi
fb
FIG. 7.
FIG. 8.
FIG. 9.
FIG. 7. The Sample is Shoveled into a Conical Heap on the Sampling
Floor. Each shovelful is dropped directly on the apex of the cone
so that the ore will roll down evenly on all sides of the cone.
FIG. 8. The Cone is Flattened by Drawing the Ore from the Center Out-
ward with the Shovel as the Sampler Walks around the Cone. The
cone is then quartered and opposite quarters are discarded.
FIG. 9. Split Shovel for Dividing the Sample.
SAMPLING
13
mixed and reduced in size in accordance with the table by
coning and quartering (Fig. 7, 8), by the split shovel (Fig. 9),
FIG. 10. Riffle for Dividing a
Crushed Sample into Halves.
FIG. 11. Riffle to be Placed on
Rubber Cloth when Used.
FIG. 12. Crusher. Sectional View.
or by riffles (Fig. 10, 11), until the quantity has been reduced
to a few ounces (Fig. 12, 13, 13a, 14), all of which will pass
through a hundred-mesh sieve; and with certain ores iron
14
METALLURGICAL ANALYSIS
FIG. 13. Pulverizer.
FIG. 13a. Bucking Plate and Muller
for Fine Grinding by Hand.
FIG. 14. Ball Mill for Soft Ore,
Coal, etc.
FIG. 15. Mechanical Grinder with
Agate Mortar and Pestle.
THE OPERATIONS OF ANALYSIS 15
ores for instance much time may be saved in dissolving the
ore if it is ground still finer in an agate mortar. Good mechanical
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