GALLERY.] natural history. (Minerals.) 83 
which was formerly considered as a variety of fluoride of calcium (fluate 
talcapatite of lime). —The only carbonate found combined with a 
chloride is the horn-lead, or chloro-carbonate of lead: the unique suite 
of crystals deposited in this Table Case is from Cromford Level, near 
Matlock. 
To the silicates with chlorides are referred the sodalite , of which, how¬ 
ever, some varieties stand in need of more accurate’ chemical examina¬ 
tion ;—the eudialyte , which occurs in West Greenland, accompanied by 
the preceding mineral substances;—the pyrosmalite ,from the iron mines 
of Nordmark, in Wermeland, massive and in perfect crystals. 
Case 58 contains the fluorides, of w r hich by far the most important 
species is the fluoride of calcium, generally called fluate of lime and 
fluor-spar: among its numerous varieties may be particularized, the 
rose-coloured crystals from Chamouni; the phosphorescent massive 
fluor-spar, called chlorophane, from Siberia; the varieties called forti¬ 
fication-fluor ; earthy and compact fluor, &c., chiefly from Derbyshire 
and Saxony.—The very scarce fluoride of aluminum, from Cornwall, 
called fluellite.—Fluoride of calcium, yttrium, and cerium;—yttrocerite ; 
and some related minerals from Finboand Brodbonear Fahlunin Swe¬ 
den .—Fluoride of sodium and aluminum, called cryolite, found in West 
Greenland: pure and mixed with brown iron-stone, galena, &c.;—the 
chiolite, from the Ural. 
Case 58 A, is appropriated to some of the silicates containing fluo¬ 
rides ;—to these belongs the topaz, here illustrated by a considerable 
series of crystals of Saxon, Brazilian, and Siberian varieties, among which 
there are several new modifications; Saxon varieties imbedded in the 
topaz rock, an aggregate of topaz, shorl, quartz, and sometimes mica ; 
Brazilian topazes, yellow and pink, imbedded in rock crystal, &c. 
—Also the pyrophysalite from Fahlun in Sweden, and the pycnite, 
formerly considered as a variety of beryl, are referable to topaz;— 
the chondrodite (maclurite, brucite)from New Jersey, and from Pargas 
in Finland; and some varieties of mica and lepidolite, ( Case 32,) likewise 
contain fluoric acid. 
Case 59 contains the chlorides.—Chloride of sodium (muriate of soda), 
or rock salt: the most interesting specimens here deposited of this im¬ 
portant mineral substance are, the crystallized varieties; the massive and 
fibrous coloured varieties, the red, chiefly from Hallein in Tyrol, the 
blue and violet from Ischel in Upper Austria; the stalactical rock salt from 
Mexico, &c —Chloride of ammonium or sal-ammoniac, from Vesuvius, 
Saint Etienne en Forez, &c.— Chlorides of lead: to these belong—the 
cotunnite from Vesuvius ; the mendipite or basic muriate of lead from 
Mendip ; and the murio-carbonate of lead (phosgenite ) from Matlock in 
Derbyshire, of w r hich most rare substance a very perfect suite of speci¬ 
mens will be found in this Case, 75 b. — Chloride of copper or atacamite, 
in crystallized splendid groups, chiefly from Remolinos, Solidad and 
Veta negra della Pampa larga, in Chili;—what was originally termed 
Peruvian green sand, or atacamite, (being obtained from the desert of 
Atacama between Chili and Peru,) is now known to be artificially pro¬ 
duced by pounding the crystallized and laminar varieties for the purpose 
of using the sand (arenilla) in lieu of blotting paper_ Chloride of 
silver, called also horn-silver and corneous silver: amorphous, bo- 
