205 
Thirty-second Species . Zeolite . 
I This species is divided by Werner into 
live sub-species, 1. Mealy zeolite; 2 Fi- 
brous zeolite; 3. Radiated zeolite; 4. Fo- 
liated zeolite ; a. Cubec zeolite. As they 
kre principally distinguished from each other 
by fracture, hardness, and lustre, we shall 
pnly observe, that the chief colours oi all are 
I- el lo wish, whitish, and reddish, with a va- 
riety of intermediate shades ; that zeolite oc- 
curs massive, in angular pieces, in balls, and 
Bometimes chrystailized in short and oblique 
four-sided prisms, and in perfect smooth 
planed cubes; that it is according to the 
'sub-species opaque, translucent, or even 
transparent ; and that it is semihard, easily 
frangible, and not particularly heavy. 
Zeolite occurs in rocks belonging to the 
newest formation, but is sometimes, though 
rarely, found in primitive green stone, either 
^disseminated, in cotemporaneous balls, or 
'lining or filling up air cavities or veins. All 
the different sub-species are natives of Scot- 
land. The mealy zeolite is found in the Isle 
jof Sky ; the fibrous and radiated in the isles 
of Canary and Sky; the foliated in Stali’a, 
[and the cubic in the same isle, and likewise 
in Sky. They are likewise met with in fee- ! 
land, in Sweden, in Germany, and the East 
Indies. Figs. 13 and 14. 
Thirty-third Species. Cross-Stone. 
The colour is a greyish-white. It occurs 
[chrystailized, either in broad rectangular four- 
I sided prisms, or in twin chrystals. 'l'iie i 
[chrystais are mostly small, and aggregated on j 
lone another. Both the internal and the ex- ! 
Sternal lustre is shining, inclining to splen- 
dent or glistening. 
The cross-stone is translucent passing to 
[.transparent, semi-hard, easily frangible, and 
| not particularly heavy. It has hitherto been 1 
found only in mineral veins, and in agate- 
j bails, at Strontian, in Argyleshire, and at 
| Andreasberg, in Iiartz, as well as some otiier 
J places. 
Thirty-fourth Species. Agate-Stone. 
The colour is a perfect azure blue, of dif- 
ferent shades. It is found massive, disse- 
minated, and in rolled pieces. The lustre is 
j glistening and glimmering. It is translucent 
on the edges, pretty hard, brittle, easily 
frangib'e, and not particularly heavy. 
The geognostic situation is not correctly 
ascertained. It is said to have been found 
I near the lake of Baikal, in Siberia, in a vein 
accompanied with garnet, felspar, and py- 
| rites. It occurs in Persia, China, Tartary, 
| and Siberia ; in South America ; but in Eu- 
I rope has only been found among the ruins 
] of Rome. 
Its beautiful colour renders it an object of 
attraction, and being capable of receiving a 
1 high polish, it is applied to various useful 
j purposes, and enters into the composition of 
j many diire ent ornaments. It is the lapis 
] lazuli of painters. Werner is constantly rnak- 
I ing additions to his species under every ge- 
I mis. 
! Of those belonging to the flint genus, 
j which are less known, and have been de- 
I scribed with less precision than the preceding, 
I are coccolite, found in Sweden and Nor- 
I way; pistaziie, found in Norway, Bavaria. 
\ and France; ceylanite, in Ceylon; enclave, 
MINERALOGY. 
in Peru; hyalite, near Franckfort; menilite, 
near Paris ; lomonite, in Lower Britanny ; 
natrolite, in Suabia ; azurite, in Stiria, Sec. ; 
andalusite, or hardspar, in Saxony, Erance, 
and Spain; chiastolite, or hollow spar, in 
France and Spain, and probably in Cumber- 
land ; scapolite, in Norway ; and arctizite, or 
wernerite, in Sweden, Norway, Switzerland, 
and lazulite. 
FOURTH GENUS. 
Clay Genus. 
First Species. Jasper. 
This is divided into six sub-species ; Egyp- 
tian jasper, striped jasper, porcelain jasper, 
common jasper, agate jasper, and opal jas- 
per. 
Second Species. Opal. 
Werner divides this into four sub-species, 
precious opal, common opal, semi-opal, and 
wood opal. 
Third Species. Pitch-Stone. 
The colours are black, green, brown, red, 
ai d occasionally grey. It occurs always 
massive in great beds and rocks. Internally, 
its lustre is shining. It is commonly trans- 
lucent in a small degree, brittle, and pretty 
easily frangible. 
Pitch-stone is fusible without addition ; oc- 
curs in beds in the newest porphyry and floetz 
trap formation ; and is found in Saxony, 
Hungary, in several of the Plebrides, and in 
Dumfriesshire. Some of its varieties bear a 
striking resemblance to pitch, from whence 
it receives its appellation. 
Fourth Species. Obsidian. 
The principal colour is velvet-black. It 
always Occurs in angularly roundish-pieces. 
Internally it is splendent. Some of the va- 
rieties are translucent, others semi-transpa- 
rent. It is hard, easily frangible, and not 
very heavy. 
Obsidian occurs insular in the newer por- 
phyry formation, arid is found in Hungary, 
Iceland, in Peru, and various other countries. 
When cut arid polished, it is sometimes used 
for ornamental purposes, and mirrors for te- 
lescopes have been formed of it. It probably 
owes its origin to fire. 
Fifth Species. Pearl Stone. 
Its colour is generally grey, sometimes 
black and red. It occurs vesicular, and the 
vesicles are long arid roundish, with a shining 
pearly lustre. It is translucent on the edges, 
not very brittle, very easily frangible, and ra- 
ther light. 
Pea;l stone is found in beds of porphyry, 
near Tokay, in Hungary, in the north of Ire- 
land, and the Hebrides. 
Sixth Species. Pumice Stone. 
Its usual colour is a light yellowish-grev, 
passing into different neighbouring shade's. 
It is small, and lengthened vesicular: its in- 
ternal lustre glistening, generally translucent 
in the edges, soft, and seldom semi-hard, 
very brittle, easily frangible, and swims in 
fluids. 
It occurs in various situations, generally 
accompanied by rocks that belong to the 
tloetz trap formation ; and t .ough usually 
classed among volcanic productions, in some 
situations it evidently is ot aquatic origin . It 
is found in the Lipari islands, in Hungary, 
Iceland, and on the banks of tne Rhine; and 
is used tor pUlishing stones, metals, glass, and 
ivory ; and also for preparing parchment. 
Seventh Species. Felspar 
Is divided into four sub-species ; compact 
felspar, common felspar, adularia, and La- 
bradore stone. Fig. 15. 
Eigh h species. Pure Clay 
Is snow white, with occasionally a yellow- 
ish tinge, and occurs in kidney-shaped pieces, 
which have no lustre, it is opaque, soils 
very little, adheres slightly to the tongue, is 
light, and intermediate between soft and fri- 
able. 
Pure clay is found immediately under the 
soil, accompanied with foliated gypsum and 
selenite, at Pialie, in Saxony, only. 
Ninth species. Porcelain Earth. 
The colour is generally a reddish-white, of 
various degrees ot intensity, it occurs mas- 
sive and disseminated ; its particles are tine 
and dusty, slightly cohering, and feeling line 
and light. 
It is found in beds in gneiss, accompanied 
with quartz and other substances, in Saxon v, 
at Passau, Limoges, and in Cornwall. In 
China and Japan, where it is called kaolin, it 
is very abundant. It forms the basis of china 
ware. 
Tenth species. Common Clay. 
This is divided into six sub-species, as 
follow : 
1. Loam, of a yellowish-grey colour, fre- 
quently spotted with yellow and brown, and 
occurring massive. It is dull and weakly 
glimmering, colours a little, adheres pretty 
strongly ro the tongue, and feels slighty 
greasy. It is often mixed with sand, gravel, 
and iron ochre. 
2. Potter’s clay is of two kinds, earthy and 
slaty. I he earthy is of a yellowish and grey • 
ish-white colour in general; occurs massive; 
is opaque, colours a little, feels somewhat 
greasy, and adheres strongly to the .tongue. 
.Slaty potter’s day is generally of a dark ash- 
grey colour, and feels more greasy than the 
preceding. It occurs in great rock masses, 
and in alluvial land. Both kinds are univer- 
sally distributed, and are of great importance 
in the arts and in domestic economy. 
3. Pipe clay is greyish-white, passing in. to 
yellowish-white, occuring massive, of a glim- 
mering lustre, and having its particles pretty 
coherent. It feels rather greasy, is easily 
frangible, and adheres pretty strongly to the 
tongue. 
4. Variegated clay is commonly white, 
red, and yellow, striped, veined, and spotted. 
It occurs massive, is soft, passing into friable, 
feels a little greasy, and adheres somewhat to 
the tongue. It is found in Upper Lusatia. 
5. Clay-stone is commonly grey or red, 
with various intermediate tints. It occurs 
massive, is dull, opaque, soft, pretty easily 
frangible, feels rather meagre, and does not 
adhere to the tongue. It forms vast rock 
masses, occurs in beds and veins,. and is found 
in Saxony, in Scotland, and in Shetland. 
6. Slate clay is of a grey colour, presenting 
several varieties. It is massive, internally 
