tion and bitter disappointment of about a thousand men, who found nothing to
reward their trouble.
"6th. That the ore will shift at different levels, from certain portions of the lode to others,
a? it has done up to the present time. More equality in its distribution may, however, be ex-
pected below the junction of the branches radiating toward the surface, when the vein will
probably fill a more uniform arid more regular channel. Some mines which have been here-
tofore almost unproductive, as the Central, California, Bullion, and others, have therefore
good chances of becoming 1 metalliferous in depth. But throughout the extent of the vein, it
is most likely that the portion which lies next to the foot-wall will continue unproductive, as
it did from the surface down to the lowest w r orks, while the entire portion between it and the
hanging wall must be considered as the probable future source of ore. As remarked in the
foregoing pages, it is also probable that repeatedly, in following the lode downward, branches
will be found rising from its main body vertically into the hanging wall and consisting of
clay of quartz. Many of them will probably be ore-bearing. Such bodies of ore should be
sought for, at all the mines, in what is generally supposed to be the eastern country. Expe-
rience in upper levels would lead to the supposition that such eastern bodies might carry richer
ores than the average of the main portion of the vein.
"7th. That the intervention of a barren zone, as is reported by good authorities to occur
at the Veta Madre of Guanajuato at the depth of twelve hundred feet, is not at all likely to be
met with in the case of the Comstqck lode. The argument which we have to adduce for this
conclusion has some weight from a geological point of view. It is a well known fact that
the enclosing rocks have usually great influence on the quantity and quality of the ores of
certain metals in mineral veins, and that a rich lode passing into a different formation fre-
quently becomes barren or poor. At the Veta Madre of Guanajuato a sudden decrease in the
yield of the ore at the depth of twelve hundred feet attends the passage of the lode into a dif-
ferent formation, which from thence continues to the lowest depth attained. No such change
can be anticipated for the Comstock lode, since the structure of the country seems to indicate
the continuity of the enclosing rocks to an indefinite depth.
" In winding up these considerations, we come to the positive conclusion that the amount
of nearly fifty million dollars, which have been extracted from the Comstock lode, is but a
small proportion of the amount of silver waiting future extraction in the virgin portions of the
vein, from the lowest level explored down to indefinite deptli ; but that, from analogy with
other argentiferous veins, as well as from facts observed on the Comstock lode, the diffusion
of the silver through extensive deposits of middle and low grade ores is far more probable
than its accumulation in bodies of rich ore."
WEST OF THE ROCKY MOUNTAINS. 37
SECTION 2.
GEOLOGICAL FORMATION, ETC., OF PACIFIC SLOPE.
REPORT OF. MR. WILLIAM ASHBURNER, MINING ENGINEER, MEMBER OF TPIE STATE
GEOLOGICAL SURVEY OF CALIFORNIA, &c.
1. Gold mining interest of California. 2. Characteristics of the gold-belt. 3. Northern
mining districts. 4. Mining in the sierras ; mills, expenses, &c.
1. GOLD MINING INTEREST OF CALIFORNIA
SAN FRANCISCO, November , 1866.
In accordance with the request you made me some time since, I beg leave to
submit the following report upon the present condition of the gold mining inter-
est of California, so far as it can be ascertained. The absence of all pfublished
documents of a reliable nature, with the exception of those recently issued by
the geological survey of the State, make it a matter of considerable difficulty to
arrive at results which shall have the merit of being perfectly trustworthy, and
the only means of obtaining them is by personal examination by competent in-
dividuals of the various gold fields throughout the State. Everybody will ac-
knowledge that accurate statistics of the results obtained throughout the exten-
sive mineral regions of the United States, particularly those where the precious
metals are found, and published under the official sanction of the government,
would be of the greatest value. If properly compiled they in themselves alone
would go far to remove the great ignorance which prevails in the public mind
with regard to many important facts bearing upon the question of mining, and
enable people to judge for themselves how far the great majority of those wild
assertions which are so frequently made by amateur visitors and newspaper
correspondents are likely to be true. It is from this class of writers who,
from their education, are not qualified to weigh and appreciate the value of
statements made to them, generally by interested and enthusiastic persons
that nearly all the information which the public now possesses of the gold and
silver mines of this country is derived.
It is universally conceded that the great objection to mining is its uncertainty,
and that, while in some cases the profits are large, the risks are more than pro-
portionably great, and the cautious capitalist hesitates before embarking upon a
mining enterprise, feeling that a shroud of mystery envelops the whole ques-
tion, and that he may be placing himself blindfolded in the hands of evil and
designing persons.
The mineral resources of many of the States have been under scientific inves-
tigation since 1830 ; but it was in 1844 that the first district for mining other
minerals than coal and iron was opened up upon the shores of Lake Superior.
Then followed a wild excitement in mines, which seems to have continued pe-
riodically since that time, upon the discovery of new and valuable mines. In
1863-'64 attention was particularly directed to the silver and gold mines of
Nevada and Colorado. No statements seemed too gross to be made, or too im-
probable to be believed. Tracts in the midst of the desert covered with sage
brush, and miles distant from any mineral-bearing vein, were located, companies
formed, prospectuses issued, and considerable sums of money actually expended
in search of mines which by no possibility could exist in such places.
A thorough survey of the various mining districts which are now attracting
so much attention both at home and abroad would confer incalculable benefit upon
the country at large, and every means should be employed to bring before the
public information of such a reliable nature that the capitalist may be guided in
his investments, and the field of the prospector for new mines be restricted to
38 KESOURCES OF STATES AND TERRITORIES
those comparatively limited districts where there is any chance of their efforts
being successful. Money and time uselessly expended in running, prospecting,
tunnels, or in sinking shafts that can never be turned to any account, is so
much loss of capital and labor taken from the productive industry of the country
at large. It was estimated that in 1862-'63 there were some 30,000 persons
in this State and on its immediate borders engaged in prospecting for gold, sil-
ver, and copper; and it is a notorious fact that not even one per cent, of the
claims discovered by those persons have ever proved remunerative to those who
invested money in their development. In 1S61-'G2 the excitement ran high on
copper, induced by the discovery of the Union mine in Calaveras county, and in
a few months the Sierra Nevada, from the foot-hills to their summits, were cov-
ered with miners fruitlessly occupied in attempting to discover new deposits?
which could be worked with a profit. A few months of scientific labor turned
in this direction would have shown how utterly futile the efforts of most of them
would prove, and how exceedingly limited in w r idth is the copper-bearing belt
of California.
The existence of gold in California was known long before the date com-
monly ascribed for its discovery. In several places along the Coast Ra; ge of
mountains between Santa Cruz and Los Angeles there were small, inconsider-
able "diggings" which were worked by the Mexicans, and some of them are
said to have yielded as much as $6,000 per annum, which, ai, that period, was
a considerable sum. The interest which is attached to these now is chiefly his-
torical, and they were generally abandoned as soon as the more extensive de-
posits which lie in the Sierra Nevada were made known.
It was on the 19th of January, 1848,* that the first gold east of the Coast
Range was discovered on the South Fork of the American river, at a place now
called Coloma. It was the result of accident, and although attempts were made
to preserve the fact a secret, the news soon spread far and wide, and by Jyly of
that year it is stated that the number of persons employed on the American river
and its branches were as many as four thousand, who were obtaining- from
$30,000 to $40,000 a day, and by November it is thought that from four to five
millions of dollars had been already extracted. It was not until a year subse-
quent to this discovery, or jn the spring of 1849, that commenced the most ex-
tensive immigration that the \vorld has ever seen. Adventurers poured into
California from all quarters of the globe: first from Mexico, Chili, and Peru ;
then from the Sandwich Islands, China, and New Holland; lastly from the
United States and Europe. During the six months between the first of July,
1849, and the first of January, 1850, it is estimated that 90,000 persons arrived
in California from the east by sea or across the plains, and that one-fifth of them
perished by disease during the six months following their arrival, such were the
hardships they had endured arid the privations to which they were subjected.
The western slope of the Sierra Nevada was soon covered with explorers,
who, with their " pans " upon their shoulders, penetrated every ravine or gulch,
"prospecting" the sands and washing the gravel wherever there was chance of
finding the precious metal. Mining towns sprang up with almost incredible
rapidity, and for several years they presented a scene of busy life. But the
shallow "diggings" soon became exhausted, and in 1851 the yield of gold was
higher than it has ever been since, amounting to at least $65,000,000. During
the last four years California has produced an average of about ^30,000,000
per annum of gold from the mines situated within her borders. At least ninety
per cent, of the total production reaches San Francisco by public conveyance,
and by some it is considered that even a larger proportion is transported in this
manner. In order to arrive at the present production, and compare it with what
has been produced in former years, we must take the amount of uncoined bul-
* History of California by Franklin Tuthill, p. 226.
WEST OF THE ROCKY MOUNTAINS.
39
lion which is known to have arrived here from the various mining districts, and
add say ten per cent, for that brought by private hands. At the same time that
this means is far from affording all the accuracy desired, it will give a closer
approximation to the truth than any other.
Referring to the San Francisco Mercantile Gazette, which obtains and pub-
lishes regularly the amount of coin and bullion received in San Francisco from
all sources, we find that the receipts of uncoined treasure from the interior, in-
clusive of that from Nevada, have been as follows during the last four years :
Production of gold from California during tlie last four years.
1862.
1863.
1864.
1865.
From the northern mines.
From the southern mines.
$30. 948, 369
! 6,601,509
$33,936,771
5,610,094
$34,782,312
5, 347, 778
$36, 649, 337
5,108,413
Total bullion receipts
Deduct bullion from Nevada.
Add 1 per cent, for Arrivals in pri-
vate hands
:J7, 549, 878
6, 000, 000
39,546,865
12,433,915
40, 130, 090
15, 900, 000
41,757,750
15, 800, 000
31,549,878*
27,112,950
2,711,295
24, 230, 090
2, 423, 009
25, 957, 750
2, 595, 775
34, 704, 866
29, 824, 245
26, 653, 099
28,553,525
Probable production for 1866, based upon the receipts of the jirst nine months
of the present year.
Northern mines, exclusive, of Nevada bullion $19,719,900
Southern mines 3,385,0]
23,104,910
Add 10 percent, for arrivals in private hands 2,310,491
25,415,401
If we compare this production with that of the Australian gold fields during
the last three years, we find that these latter have produced as follows :
1863 1,627,066 ounces.
1864 : 1,545,450 ounces.
1865 1,556,088 ounces.
The Australian gold is of remarkable fineness, averaging about T 9 2 oV' an( ^
worth, consequently, $19 04 an ounce. This would be, in our currency, as
follows :
1863 $30,984,336
1864 29,425,368
1865 29,627,916
The mineral statistics which are published annually by the colony of Victoria
give much valuable information concerning the present situation of the gold
mining interest in Australia, and from them the above information has been
gathered. The average earnings of the miners in this colony have been as
follows during the last three years :
Alluvial miners. Quartz miners.
1863 $487 45 $596 24 per annum.
1864 296 69 632 44 per annum.
1S65 323 32 491 36 per annum.
40 RESOURCES OF STATES AND TERRITORIES
We have for this coast no statistics which will enable us to arrive at the
average earnings of the miners in California with the same degree of accuracy,
but there does not seem any reason to suppose that they are greater here than
in Australia.
During the year 1864, of 1,54/5,450 ounces of gold exported from this colony,
about one-third, or 503,618 ounces, were supposed to have been derived from
the quartz mines. This proportion of two to one must be very nearly the
relation which the gold produced from the placer diggings of California bears
to that from the quartz mines, which probably does not exceed $8,000,000 or
$9,000,000 per annum.
2. CHARACTERISTICS OF THE GOLD BELT.
The auriferous belt of California extends from the Tejon pass, in latitude 35,
to the northern extremity of the State, or for a distance of about five hundred
miles. The principal gold fields, however, and that portion of the State which
has produced most largely, lies between about latitude 37 and the North Fork
of the Feather river, or over a distance not exceeding two hundred and fifty
miles. Towards the south this gold-bearing range is narrow, rarely exceeding
twenty-five miles in width. As we proceed north, however, it widens rapidly,
and along the Feather and Yuba rivers it reaches from th*e lower foot-hills of
the Sierra Nevada to the central axis of the mountains, or over a width of fifty
miles from east to west. There are other diggings in the more northern part of
the State, bounded by the Trinity, Upper Sacramento, and Klamath rivers,
which at one time were valuable, and yielded largely, but now the principal in-
terest attaches to those deep placers lying between the forks of the Yuba, those
deposits which underlie the volcanic formation in many places on the auriferous
belt as far south as Tuolurnnc county what are known as the cement diggings
and the quartz mines which are to be found between Tulare county on the
south and Plumas county on the north. The " shallow diggings," which were
formerly so immensely rich, and which attracted the first attention of the miner,
are now, for the most part, hopelessly exhausted ; but, notwithstanding this,
by far the greater proportion of the total gold production of California is still
derived from the " washings," hydraulic and others ; and this will undoubtedly
continue to be the case until those immense auriferous deposits lying in the
northern part of the State, principally in Nevada county, are exhausted. No-
thing but an accurate survey will give any thing like an approximation as to the
length of time which will be required to work them out at the present rate. Now
we have only the wildest conjectures and statements, the result of hasty exam-
inations, as to their extent and the probable amount of gold contained in them.
At the present time, about eighty per cent, of the gold produced from the mines
of California is derived from those lying north of the Mokelumne river, and the
production from the southern mines, or those situated between Mariposa and
Calaveras counties, is decreasing every year. Probably only about one-third
of the gold productions of California comes from the quartz mines, leaving two-
thirds to be furnished by the placer and cement diggings, or those sources of
supply other than veins. Unfortunately, too little of a reliable nature is now
known with regard to these latter for me to venture upon an intelligent expo-
sition of them; but enough is known concerning the former to predict that
quartz mining will continue to be one of the most lasting, as well as profitable,
interests of this State, and there now seems no reason to anticipate that Cali-
fornia will cease to be one of the principal gold-producing countries of the world
for many years to come. I will therefore confine myself entirely to a descrip-
tion of a few of the more noted quartz mines of the State, showing, when it is
possible, the amount of profit realized from the working of the quartz, its average
yield, the expenses attending the milling and mining, and giving such other
facts as may be considered as illustrating the present condition of 4his industry
WEST OF THE ROCKY MOUNTAINS. 41
The principal quartz mining districts of California are in Tulare county, about
Clear creek ; in Mariposa county, on the Mariposa estate and its immediate
neighborhood, and also round about Centreville, north of the Merced river; in
Tuolumne county, within a few miles of Sonora, at Soulesbeyville, and near
Jamestown ; in Calaveras county, at Angels ; in Amador county, near Jackson
and Sutter creek ; in El Dorado county at Logtown and vicinity ; in Nevada
county at Grass valley and Nevada; in Sierra county within a few miles of
Downieville ; in Plumas county at Indian valley and on Jamieson creek. These
localities were nearly all centres of placer diggings before quartz mining became
so important. an industry. The width of this quartz-bearing range is, however,
much narrower than that occupied by the placer workings, and while rarely more
than twentv miles in width, is generally much less.
The number of veins in this belt is almost innumerable, but the proportion of
those which contain gold in sufficient quantity to pay is exceedingly small.
The most reliable publication which has recently appeared with regard to the
quartz veins of California was issued by the State geological survey in April,
1866. The statistics were compiled by Mr. A. Rdrnond, and give several im-
portant particulars with regard to the mills and mines in the region between the
JMerced and Stanislaus rivers. The district embraced by this report is about
thirty miles long by from fifteen to twenty in width. Seventy-seven mines and
sixty-five mills were examined and reported upon, and of these fifty-six mines
and twenty-three mills were being worked at the time of Mr. Remond's visit.
So far as the mere number of the veins is concerned this region probably con-
tains as many with features sufficiently promising to warrant exploration as any
other district of eo|ual size in California. The actual amount of capital invested
in the erection of the mills examined has been $430,300, and in addition to this
a considerable sum has been spent in the construction of roads, flumes, and
ditches, and by far the larger proportion of this whole sum has been expended
since 1862, particularly in the years 1864-'65, and therefore several of the
mills may be considered as experimental, and the veins upon which they are
situated as not having been proved sufficiently to be able to state whether the
yield as given to him by the proprietor will be lasting. It is certain that the
gross production of this region from the quartz mines now being worked is not
very large, nor does it as yet compare favorably with several other districts not
nearly so extensive. The greater number of these veins vary in width from about
one foot to two feet six inches, while in one case there is a vein noted which is
twenty-five feet in width and another fifteen feet. The average width of all the
veins examined would appear to be about three feet. The " country rock," or
the rock in which the quartz veins of California are incased, is for the most part
either slate, granite, or greenstone, and it is not yet determined which of these
three formations can be regarded as furnishing the most prolific mines, for we
have in each of them veins which have produced largely, and still are continu-
ing to do so, though several of them have attained a considerable depth.
In Mariposa county, and particularly upon the Mariposa estate, the most noted
veins are in the slate and have a direction and dip nearly coincident with the
general stratification of the enclosing rock. The principal mine in the district
is the Princeton, which lias produced between two and three millions of dollars.
It was first worked in 1852, and the quartz is said to have yielded as high as
seventy-five dollars per ton for a short time, but this large return was probably
owing to the various sulphurets contained in the quartz and associated with the
gold having been more or less decomposed near the surface by atmospheric
agencies, and the gold liberated by this means, so that the outcrops of the vein
were far above the average richness of the quartz. Since 1861, arid until within
the last year, the rock from this vein has yielded an average of $18 34 per ton,
while the expenses of mining have been about $6, and the cost of milling $3 25.
42 RESOURCES OF STATES AND TERRITORIES
This would show a profit over and above the expenses of working of nearly 50
per cent.
In the latter part of 1864 the yield of the quartz from this mine fell, almost
without giving any warning, from $40 to $6 per ton, and for some time ceased
to pay expenses. During 1865 the yield was better, but it is still far from
affording as satisfactory results as in former years. The depth of the main
shaft is nearly 650 feet, and the length of the underground workings not far
from 1,400 feet. It is by no means certain that this mine is exhausted, and that
another sinking will not open up new bodies of valuable ore. There are too
many examples throughout California of mines falling off rapidly in their yield,
and meeting with barren zones of quartz, both in depth and 'on the longitudinal
extension of the vein, for any one to state positively that a lode which possesses
so many characteristics of permanence as the Princeton should be abandoned,
and that it will never again prove remunerative as in past years.
Near the northern end of the Mariposa estate are two mines known as the
"Pine Tree" and "Josephine," which have been worked for nearly sixteen
years. When this property passed into the hands of General Fremont these
mines were considered as being among the richest as well as most reliable in
California, and it is perhaps to be regretted that the anticipations formed at that
time have never been realized, for it is mainly owing to their failure that so
much discredit has been cast upon the quartz mining interest both at home and
abroad. These two mines are situated in close proximity to each other, and
although they have never .been connected by underground workings they prob-
ably are upon one and the same vein. The Pine Tree vein has a direction
nearly the same as that of the slates in which it is encased, or about northwest
and southeast, while the Josephine runs more nearly east and west, and the
axes of these two veins would form at their junction an angle of about forty
degrees. Work is just now abandoned upon this latter mine, but is being ac-
tively prosecuted on the former, and the quartz is said to be paying better
than was formerly the case, owing to a more careful selection and thorough
metallurgical treatment. The outcrops of these veins are at an elevation of
about fifteen hundred feet above the Merced river, and can be observed from a
long distance to the north. Neither of them can be followed or traced individu-
ally for any great distance upon the surface in such a manner as to preserve
their identity, and in this respect they in nowise differ from the great majority
of gold-bearing veins in California. In fact, the experience of mining in this