NATURAL HISTORY. 
67 
GALLERY.] 
stone, &c.—the klaprothite , called also blue spar, and azurite, and 
is therefore sometimes confounded with the lapis lazuli;—together 
vrith some other substances of which no exact analyses have as yet 
been published, though they are known to be chiefly composed of alu¬ 
mina in combination with phosphoric acid, such as—the calaite, or real 
turquois (firuzah in Persian), an opaque gem found chiefly at Nisha- 
pur, in the province of Khorasan, Persia, in nodules or as small veins 
traversing a ferrugino-argillaceous rock, and greatly esteemed on ac¬ 
count of its beautiful blue colour, which will in most cases be sufficient to 
distinguish it both from the blue silicate of copper and from fossil bones 
(particularly teeth) impregnated with blue phosphate of iron or carbonate 
of copper, some of which substances are vulgarly called occidental tur¬ 
quoises.—The hakoxene , a rare substance of a crystalline diverging- 
fibrous structure and yellow colour, found in the fissures of argillaceous 
iron-stone, near Zbirow in Bohemia;—and the childrenite from Tavi¬ 
stock, in Devonshire : both which mineral substances contain alumina 
and oxide of non combined wnth phosphoric acid, but require to be sub¬ 
jected to closer chemical examination.— Phosphate of magnesia: the 
very scarce wagnerite, from the valley of Holgraben, near Werfen, in 
Salzburg. 
In two of the supplemental Table Cases (57 A and B) in this room 
are deposited such phosphates as are combined with chlorides. 
Case 57 A. Pyromorphite, a combination of phosphate of lead and 
chloride of lead, generally divided into brown lead ore and green lead 
ore: among the varieties of the former, the more remarkable are the 
large six-sided prisms from Huelgoet in Brittany; of the latter we 
have the massive botryoidal ( traubenertz ), the spicular, and crystallized 
varieties, of various shades of green passing into greenish-white, into 
yellow and orange. To these are added phosph-arseniates and also some 
arseniates of lead, from Siberia, Cumberland, Saxony, &c., whose che¬ 
mical constitution is not yet perfectly understood; in 
Case 57 B. Phosphate of lime combined with chloride of calcium, 
in some varieties of which this latter constituent is replaced by fluoride of 
calcium : among the specimens may be particularized several very scarce 
and interesting crystallizations of Werner’s apatite, such as the large vio¬ 
let-coloured crystals from St. Petersburg; the groups from Ehrenfrie- 
dersdorf, Maggia on St. Gothard, Traversella in Piedmont, &c.; the 
variety called asparagus-stone, from the Greiner in Tyrol, and particularly 
the specimens from Jumilla in Murcia; the Norwegian apatite called mo - 
roxite; also the phosphorite or fibrous and compact phosphate of lime, 
and the pulverulent variety, known by the name of earth of Marmorosh, 
which w 7 as formerly considered as a variety of fluoride of calcium (fluate 
of lime). 
Case 58 contains the fluorides, of which 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.— Fluoride of calcium, yttrium , and cerium •—yttrocerite ; 
and some related minerals from Finbo and Brodbo near Fahlun in Swe- 
