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placed horizontally; and which are only, he
says, distinguishable from mica as they are
duller, and are oily and unctuous.

" I have similar crystals, which are found in-
laid in topazes and emeralds of Siberia; and as
I perceive the insensible transitions from pure
mica to this unctuous mica, I look upon this
last as a simple modification, or perhaps the
commencement of the decomposition of the real
mica.

" Saussure has observed on Mount Cervin,^
near Mount Rosa, a steatite which he has called
specular. It terminates the last rock before the
snow. He has given it that name because its
surface is as smooth as a mirror, and as polished
as this species of rock admits. Its colour is a
very dark bottle-green; its fracture irregularly
schistose ; it is soft, and is easily scratched with
a grey streak*.

"Saussure has elsewhere seen, and particu-
larly near the convent of Mount St. Bernard, a
large rock of a quartzy nature, whose entire
surface is polished so as one may see one's self
in it, as in a looking-glass. He justly regards
this phenomenon as an effect of crystallisation.

* See Sams. 2258.
V01. I. Y



OMAIN IV. TALCOUS.



<c I have found in the lead-mine yielding silver
of Kadainsk, in Daouria, near the river Amur, a
steatite of a very remarkable variety. Although
of a tolerable firmness, it is so unctuous, that in
drawing the finger along its surface, it gives it
the same gloss as it would to a piece of soap.
It is of a perfectly homogenous tissue, although
composed of very distinct alternate layers, from
half a line to a line in thickness, of which some
are of a beautiful milk white, and the others of
an ochre yellow. These layers, although con-
torted, are parallel among themselves ; and as it
generally presents segments of concentric cir-
cles, the stone has the appearance of petrified
wood.

" I had brought away two specimens, and I
wished to wash one of them ; but it was scarcely
wet before it broke into little fragments, the size
of a pea, all the fractures of which were per-
fectly conchoidal, and the angles very sharp.
The mark of the layers has almost entirely dis-
appeared in these fragments, which have as-
sumed a uniform tint, between white and yellow.
The thinnest fragments are translucent on the
edges."*

This stone must resemble the circular talc
described and figured by Wallerius.

* Patrin Min. i. lp5.



MODE IV. STEATITE. 323

The softer steatite chiefly occurs in veins in
serpentine, and in nodules in basaltin* and
Saussurite : but the harder forms rocky masses,
else the substance could not have appeared with
propriety in the present treatise. The rock of
hard steatite, described by Saussure, may serve
as an example: he discovered it on his journey
between Nice and Genoa, on the sea-shore, of
the height of 15 or 20 feet. The exterior surface
is shining : here reddish, there of a silvery hue,
and rather soft to the touch.

" It splits in irregular fragments, rather ap-
proaching to the rhomboidal. Its fracture is
schistose, irregular, and otherwise very like its
exterior surface : it gives a grey streak ; is soft,
and rather heavy ; odour earthy ; easily melts
into a grey glass, which sinks on the support;
it has no effect on the magnet.

" The rock composed of this stone is divided
by veins of spar and quartz; and this last con-
tains, in places, pieces of green hornblende.

" Some parts of this rock are of a bright deep-
brown violet colour. The fracture presents schis-
tose laminae, irregular, small, and often con-
choidal ; the streak is of a reddish grey ; like

* Fine specimens of this kind are brought from the isle of Rach-
lin, on the north of Ireland, celebrated as the retreat of Robert I.
king of Scotland from the English power.

y 2!



324 DOMAIN IV. TALCOUS.

the other, it is soft, rather heavy, and very fusi-
ble, but its glass is black, while that of the other
is grey ; it is doubtless a superabundance of iron
which gives these pieces their red colour, and
causes their glass to be black ; but this iron is
under the form of oxyd, or what was called calx;
for neither does this stone affect the magnet.

" This rock is succeeded by another, smaller,
and of the same nature, on which stands a little
chapel, dedicated to St. Andrew, which has given
it the name of Scoglio di St. Andrea.

"This rock stretches along the sea; it is
afterwards covered by a granular serpentine,
similar to that of La Garde, 1342, which, like
that, splits in small polyhedral fragments, irre-
gular, the faces coloured by ferruginous irides-
cences, and which falls like it in decomposition.
This same stone is still seen in the ascent beyond
Peggi."*

STRUCTURE I. SOFT STEATITE.

White soap-rock, from Cornwall.

The same, mottled with red or blue, from the
same country.

The same, rather harder, from Portsoy, in Scot-
land.

* Sauss. 1357.






MODE IV. STEATITE.



The same, with elegant variegations of red. t
The same, greenish, in serpentine.
White steatite, with black dendrites, from Sax-
ony.

Karsten mentions a massive steatite, which is
found in extensive strata at Thierschein; but he
does not distinguish between the soft and the hard
kinds *.

' Steatite, crystallised in hexahedral prisms of a
middling size, terminated by six planes, the edges
formed by the meeting of the lateral and acumi-
nating planes, truncated, but in other respects cir-
cumstanced as usual, in massive steatite, from
the same place." f

Soft steatite, called Spanish chalk, but probably
from the Alps of Dauphiny.

Soft steatite, from New Caledonia, where the
savages mix it with their food. This custom is
also known to the savages on the Orinoco; nor
is it unknown in the German country of Lusatia.
The Arabs are said to use it in their baths instead
of soap, and it is also used as fullers' earth.

Steatite, in basalt, from Skey, and other western
isles of Scotland.

* Leske, 131. f Ibid.



DOMAIN IV. TALCOUS.



STRUCTURE II. HARD STEATITE.



Distinctions. Soft steatite may be scratched with the nail;
but when the coherence is such that this substance
does not yield to the knife of copper, or even
sometimes of steel, it must assume the name of
hard steatite ; the hardness extending from the
gypsic to the marmoric, and even to the basaltic.
It must here be premised that the little Chinese
idols, formerly supposed to be of indurated steat-
ite, are now known by chemical analysis to belong
entirely to the Argillaceous Domain; a proof,
among many others, of the insufficiency of exter-
nal characters, and that mineralogy can derive no
certain light, except from the lamp of chemistry.

Aspect 1. Compact. Hard steatite, approach-
ing to serpentine, of a dark green colour, with
chlorite, from Silesia.

Of a pale green, with black lines, from the Alps
of Dauphiny.

The early writers sometimes confound the hard
steatite with ollite.

Aspect 2. Laminar. The plates are com-
monly curved, and occasionally have a fibrous
fracture. It is translucent on the edges, and






MODE V. OLLITE.



sometimes entirely. Mr. Kirwan calls it foliated,
or striated steatite ; and says that it is generally
found in independent amorphous masses, some-
times investing or intersecting serpentine.

" Leek green, inclining to olive green, curved
foliated steatite, from Norway. *

" Mountain green, partially sprinkled with
black, foliated steatite, from Z6bliz."f



MODE V. OLLITE.

Texture, earthy, rather schistose. Characters.

Hardness, cretic or gypsic. Fracture, un-
even, somewhat slaty. Fragments, amorphous,
blunt, often laminar.

Weight, carbonose, sometimes granitose.

Lustre, dull, sometimes glimmering, unctuous.
Opake; if translucent on the edges it approaches
to hard steatite.

The colour is often greenish grey, or blackish
green; sometimes yellowish, or reddish. It is
often spotted, like a snake, whence the ophites
of the ancients, which certainly belonged to this
kind, and not to the green porphyries, as has
hitherto been supposed by a long train of mi-
neralogists, copying each other. It differs from

* Leske, 131. f Ib.



328 DOMAIN IV. TALCOUS.

serpentine, by the grain being finer and fatter;
and is more easily cut with a knife.

That of Chiavenna has been analysed by
Weigleb, who found, magnesia 38, silex 38,
argil 6, iron 15. Who would suppose, after this
analysis, that Werner should place this sub-
stance among the argillaceous, with an equal
contempt for chemical principles, which can
alone afford any solid foundation for the science,
as when he places the corindon gems among
the siliceous, though they do not contain one
atom of silex ! The paternal love of his own
system must be violent indeed, when it leads to
such contempt of every principle on which the
science has been founded.

This substance has commonly been called
lapis ollaris, which has been translated pot-stone,
from the use to which it has been applied, even
Ancient. f rO m remote antiquity, Pliny mentioning that
the stone of the isle of Siphnus, in the Grecian
Archipelago, and the greenish stone of Como,
in Italy, were both used in his time to make
vessels for cooking food. Wad, in his account
of the Borgian museum, mentions several Egyp-
tian monuments of ollite, chiefly small statues.
The varieties are :

Ollite, of a blackish green, with grass green
spots.



MODE V. OLLITE. 329

Ollite, of a yellowish green.

Of an olive green, with larger and smaller
veins of a greyish black, spots of a liver brown,
and small specks of an Isabella yellow.

Of an olive green, with grass-green spots.

Semi-transparent, of an emerald green, with
irregular oblong spots of an ochre yellow. This
would rather seem to be a hard steatite.

Of a greenish grey, with a cast of blue.

Of a yellowish grey, verging on Isabella co-
lour.

Of a foliated structure, resembling, as he adds,
the laminar steatite of Karsten.

Two other relics are of a brownish black, and
a greenish black ; in a third, mingled with a few
grass-green spots.

The learned author has added the following
observations :

" To this class, which affords so many Effvp- Thebaic

J &J r stone.

tian remains in the Borgian museum, belongs
the Thebaic stone of the ancients, which con-
stituted large portions of mountains, the quar-
ries being mentioned by Theophrastus. Pliny
has observed that it was black, or of a dark co-
lour, and marked with golden spots *. He
also observes that it yielded a juice, whence

* xxxvi. 8, 22.



330 DOMAIN IV. 1-ALCOUS.

it must have been soft, and was used for mor-
tars, as, from its natural benignity, it seemed
peculiarly fitted for pounding medicines. If we
compare these indications with any Egyptian
stone, we shall find they agree with this only,
the colour being frequently black or dark, and
sometimes spotted with golden mica, of a soft
nature, and used for mortars, one of the remains
being of that description/'

It has already been mentioned in the descrip-
tion of green porphyry, that the Theban ophite
of Lucan, and the dark ophite of Pliny, were
spotted ollites, which in fact bear far more re-
semblance to the skin of a snake than green por-
phyry, to which the appellation has been care-
lessly transferred.

Boot's Boot, physician to the emperor Rodolph II.

1576 1612, published a treatise on precious
stones, certainly very able and acute for that
period* for he was the first who, in treating of
the diamond (lib. ii. c. 1. p. 117- edit. 1636.
8vo.), remarked that it belongs to the inflam-
mable substances ; an idea also, upon quite dif-
ferent and original grounds, adopted by the
great Newton. This author, after quoting Di-
oscorides and Pliny, observes that the ophite is
a grey stone, found at Zoblitz, and used in
making pots or vases, and the reputation of its



MODE V. OLLITE. 331

medical qualities continued to his day. The
ollites of Zoblitz in Saxony are still well known.

Laet, in his treatise on Gems, 1647, 8vo.
p. 168, rather confuses the question, as usual
with commentators, but quotes Gesner, who
seems the fountain of the error, that ophite is a
green marble, or porphyry, owing to his merely
reading one sentence of Pliny, without adding
the subsequent context. Laet says, that he re-
ceived from Crusius a fragment upon which he
had written, " A fragment of the cup of Ed- E ^Pj5Jf|fy-
ward IV. King of England, formed of the stone
called ophites, useful against poison, the gift of
H. Morgan, 1581." This fragment was of a dull
green colour, very little translucent, sprinkled
with crystalline spots of a bright green, and
pretty conspicuous if held before the light. This
may have been a serpentine, or ollite, with hex-
agonal spots of green mica, or steatite. The
erroneous application of the term ophite by the
greatest mineralogists, for more than a century,
will excuse even a repeated confutation.

The ollite of Como, which is still in use, is of sites.
a foliated texture, and greenish grey colour.
That of Saxony, used for tea-caddies, milk-pots,
and several other purposes, is of a greenish grey,
with irregular veins and spots of black. The
noble house of Inverary, the seat of the duke of



DOMAIN IV. TALCOUS.



Argyle, is constructed with a dark ollite, of which
there are quarries in the neighbourhood; and
which has likewise been formed into punch-bowls
and vases. It is also said that the cathedral of
Bergen, in Norway, is built of ollite.

In the middle ages, Chiavenna had supplanted
Como in this article of commerce, the quarries
of ollite being at Pleurs, a town about two miles
to the north-east; but the excavations were con-
ducted with such little care, that in 1618 the
hill fell down, and buried the city, with the
greater part of the inhabitants*. Near Oletza,
in Corsica, ollite is found of a bright olive green,
and is worked by the lath like the others. Ro-
ziere, in his interesting memoir on the valley of
Cosseir, in Egypt, mentions that the Arabs make
little vases of an ollite, which they find in that
country. The celebrated calumet f, or pipe of
peace, of the American savages, is of a greenish
grey ollite, with reddish veins and spots, and is
cut with the knife into a not inelegant form,
with a second cavity adapted to receive a long
reed, which serves for what is called the stem.
On the west of the Missouri the savages are said
to use a red serpentine for the same purpose.

* See the affecting detail of this event in Burnet's travels,
t So called from the French chalumeau.



MODE V. OLLITE.



333



Nor is the culinary use of ollite unknown among
these rude tribes.

Greenish grey ollite, spotted with golden mi-
ca, from Egypt.

The same, spotted with green scales, from the
same.

The same, spotted with black, from the same.

These varieties belong to the real ophites of
the ancients.

Greenish grey ollite, with black veins and
spots, from Zoblitz, in Saxony.

Yellowish, from the same.

Light grey, from the same.

The same, from Como.

Yellow and green ollite, from Finland.

Karsten has the following specimens :

" Greenish white, reflecting changeably into
silvery white, pot-stone, from Ochsenkopf.

" Greenish grey, spotted with reddish, pot-
stone, from the same place.

" Very thin slaty pot-stone, with inlaying
garnets, from Tyrol.

" Thin and curved slaty pot-stone, mixed
with quartz, from the same place. .

" Very thick and curved slaty pot-stone, from
Ochsenkopf."

These examples are rather singular, and the



334 DOMAIN IV. TALCOUS.

first may possibly be the white ophite of
Pliny*. '

Ollite, in rude pots, &c. from the extreme
northern regions of America.

The same, formed into the heads of calumets,
or pipes of peace, from North America.



MODE VI. SERPENTINE.

Characters. Texture, small-grained, compact.

Hardness, marmoric. Fracture, rather un-
even, sometimes scaly, sometimes flatly con-
choidal. Fragments, amorphous, rather blunt.

Weight, granitose, sometimes siderose.

Lustre, dull, sometimes rather glimmering.
Opake; often faintly translucent on the edges.

The colours of this noble rock are surprisingly
rich and various. They are thus enumerated
by Mr. Jameson :

" Its ^principal colour is green, of which it
presents the following varieties: leek, oil, and
olive green; from oil green it passes into moun-
tain green, and greenish grey ; from leek green

* Saussure says, 1724, that near Zumlocli, on the river Egina,
there is a quarry of ollite, the stone being composed of whitish
translucent talc, grey mica, little pyrites of a golden yellow, some-
times iridescent, and a little lime.



MODE VI. SERPENTINE. 335

it passes into greenish black; from greenish
black it passes into blackish green ; sometimes
it occurs yellow, and rarely yellowish brown:
further, red, of which it presents the following
varieties; blood red, brownish red, peach-blos-
som red, and scarlet red.

" The peach-blossom, and scarlet red colour,
are the rarest.

" The colour is seldom uniform ; there are
generally several colours together, and these are
arranged in striped, dotted, and clouded deline-



ations."



It is a primitive rock, and appears to be stra- primitive,
tified, but, like granite, very indistinctly. It is
an important geological observation, that some
rocks, particularly the calcareous, assume the
appearance of being stratified, by incipient de-
composition, as Ramond remarked in the Py-
renees. But may not even this circumstance
be considered as a proof of original stratification,
merely rendered more apparent by the decay of
the softer parts; as, if there were no original
joints for the humidity to enter, the decompo-
sition would only occasion irregular crevices ?

Werner and his disciples have observed near
connexions between the formations of trap or
basaltin and serpentine. When the former con-

lins an excess of magnesia, it becomes a re-



336 DOMAIN IV. TALCOUS.

markable pierre de come of Saussure, here called
Saussurite, in honour of that great observer.

Patrin is perhaps the only professed writer on
mineralogy who has enlivened his subject by
variety of illustration; and as his work will pro-
bably never appear in the English language, his
descriptions, which often contain anecdotes de-
rived from his own extensive travels, are given
with the less hesitation.
Patrin's "Serpentine owes its name to its colour; it

account.

is generally green, often spotted with white,
yellowish, brown, and sometimes reddish marks,
which gives it some resemblance to the skin of
serpents. Its green colour is owing to iron,
which is abundant in it, and but little oxygi-
riated*.

" It is generally opake ; but some of its parts
are occasionally semi-transparent. Though not
very hard, it receives a fine polish, which has an
unctuous appearance, like jad.

" Serpentine is a primitive rock; the forma-
tion has been a little posterior to that of massive
granite, for it is very rare to find them united.
It has been contemporary with that of micaceous
and calcareous schisti, with which it is some-
times seen confounded, whether in the same or

* This seems rather doubtful.



MODE VI. SERPENTINE. 337

in distinct beds, but which alternate, and are
reciprocally overlaid, the one on the other.

" Serpentine is rather more abundant in na-
ture than traps and corniennes ; and much more
so than porphyries.

" It is generally found in amorphous masses,
like porphyries, and seldom in distinct beds.
It forms chains of hills or mountains, but little
elevated, at the foot of great granitic chains : it
is very rare to find it in very lofty mountains,
and still more rare to see it form beds (arrects)
approaching a vertical position, a position so
common to micaceous schisti.

" In regard to the little elevation at which
serpentine is generally found, there is an excep-
tion, perhaps unique and very remarkable, in
Mount Rosa, where there are summits which Mount Rosa.
surround the central part of that mountain,
which are composed of serpentine, although
their elevation is from 1500 to 1700 fathoms, and
upwards ; and what is also very remarkable, is,
that the beds of this rock are there in a position
most often horizontal. But even this position,
and the presence of serpentine at this great ele-
vation, are owing to the same cause, which I
shall explain in treating of geology ; for this
mountain, become famous since the travels of
Saussure to that region, and which is one of the

VOL. i. z



338 DOMAIN IV. TALCOUS.

most extraordinary existing, is also one of those
which will throw the greatest light on the mys-
tery of the formation of primitive mountains.

" Europe is that part of the terrestrial globe
in which most serpentine is found j the whole
front of the Alps, which looks towards Italy,
offers it almost every where, although these
mountains show but very little of it towards
Swisserland.

" It extends throughout Italy, where it is
called gabbro. One of the finest is that of the
hills of Improneta, near Florence : it contains a
good deal of that green, semi-transparent, and
satiny substance, which Saussure has called
smaragdite, on account of its fine colour of eme-
rald green.

" France has some mountains of serpentine,
especially in Limousin.

" The finest serpentines of Spain are from
Sierra-Nevada, two leagues from Grenada : they
have a green base, filled with glistening plates,
of a yellowish colour. Superb columns have
been made from it, which decorate the churches
and palaces of Madrid.

" It is almost entirely wanting in northern
Asia, with the exception of the eastern part of
the Ural mountains, which separate Siberia
from Europe. There are some hills which, at



MODE VI. SfiRPENTINF.. 339

great intervals, accompany their base, following
their direction from north to south. There are
even some detached branches, which appear
near Tobolsk, which is not far from those moun-
tains.

" But from thence to the river Amur, that is
to say, in a space of about a thousand leagues,
scarcely any vestiges are found, in the great
chains of Altai, Sayannes, and in the mountains
of Daouria.

" The serpentines most known are those of
Sahlberg, in Sweden, and of Zeoblitz, in Saxony,
from which vases are turned of every kind, which
are spread over Europe*.

" The serpentine of Bareith is filled with gar-
nets of an irregular form, generally of the size of
a pea: they are sprinkled in an equal manner
in the mass, and when the stone is polished it
presents a very agreeable mixture of spots, of a
fine red on a green base. Trinkets and other
ornaments are made of it..

" Saussure has observed several serpentines, in
rolled blocks, on the shores of the lake of Ge-
neva : they are remarkable by their specific gra-
vity, which is greater than that of all other ser-
pentines. He saw some soft, and some hard.

* It is commonly an ollite.
Z 2



DOMAIN IV. TALCOU3.



The softest is foliated, and its specific weight
exceeds 3000, which is the weight of oriental
jad. It is this softest variety which the best
resists the action of fire.

u Some of the blocks found in the valley of
Chamouni present a green serpentine, marbled
with white, like the serpentine of Saxony ; others,
a green serpentine also, but mixed with shining
plates of green talc, threads of asbestos, and of
brilliant and golden amianthus, with laminar
crystals in the form of flattened parallelepipeds.
These crystals have neither the hardness of
schorl, nor the characteristics of hornblende;
they melt into a white amel, while hornblende
always gives a black glass. The plates of green
talc are infusible ; and the serpentine which
constitutes the base of the stone melts, in bub-
bling and emitting little sparks.

" These fragments proceed from some hills, or
considerable masses, which have been destroyed
by time. Saussure saw, near Chiavenna, in the
country of the Grisons, entire mountains of ser-
pentine and ollite, which were only heaps of in-
coherent blocks.

" The summit of the mountain of Garda, near
Genoa, is composed of a serpentine, which Saus-
sure has called granular : it is of a deep grey
green, with unequal fracture, dull, earthy, af-



MODE VI. SERPENTINE. 341

fording an argillaceous smell, and melting under
the blow-pipe into a black glass. Its exterior
is covered with a coat of rust.

" The observation of the characters of this
rock is important, as it shows the transition of
serpentines to corneennef. It is absolutely mid-
way between these two sorts of rocks.

" The beds of this serpentine alternate in the
mountain with beds of calcareous, quartzy, and
micaceous schistus ; and with beds of primitive



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