106 NATURAL history, [^LONG 
placed the olimne^ which, in its purer state^ is denomi¬ 
nated chrysolite or peridot, and when protoxide of iron is 
predominant^ has, by some, been called hyalosiderite. 
Case 26. Silicate of zinc, called also electric or sili¬ 
ceous calamine, the finest specimens of which are those 
from Siberia and Hungary; the variety called willemite, 
from Aix-la-Chapelle.— Silicate of manganese, of which 
there are several varieties (some of them only mechanical 
mixtures of this silicate, of carbonate of manganese, and 
quartz), which have received particular names, such as 
allagite, rhodonite, &c. Silicate of cerium or cerite, from 
Bastnas, Sweden,—with which is placed the rose-coloured 
substance called thulite, found with blue idocrase in Telle- 
marken, Norway.— Silicate of iron, to which belong the 
hisingerite, sideroschizolite, chlorophceite, and stilpnomelane* 
— Silicate of copper, or siliceous malachite, formerly called 
chrysocolla and copper green ; to which is also referred the 
dioptase or copper emerald, a scarce substance from the 
Kirguise country in Siberia— Silicate of bismuth, also 
called bismuth-blende, a rare mineral substance in hair- 
brown globules from Schneeberg, Saxony.— Silicate of zir^ 
conia, to which belong Werner*s common zircon, and some 
hyacinths, from Ceylon, Auvergne, Chili, the Lake Ilmen 
in Siberia; also the variety called zirconite from Fried- 
ricksvarn in Norway, &c.;—the blue zircon from Vesu¬ 
vius.— Silicate qf alumina: to this belong the hyanile or 
disthene, and its varieties, the bucholzite and the sillimanite; 
and also the scarbroite, halloysite, lenzinite, &c.; together 
with such varieties of clay as are chemical combinations of 
alumina and silica. 
For the subdivision into groups of the Silicates with 
several bases, the reader is referred to the tickets in the 
interior of the following ten Cases, which contain this ex¬ 
tensive class of mineral species. 
Case 27 contains the following zeolitic substances: 
apophyllite, or ichthyophthalmite, in fine crystals, from 
Hesloe in Faroe; with stilbite; with tessellite of Brewster, 
with poonahlite of Brooke, &c.; a variety of apophyllite, 
formerly called albine, by Werner;— chabasite or chabasie, 
in groups of primitive rhomboidal and modified crystals ; 
—the variety called haidenite from Baltimore;— mesotype 
