34 
SALOON. 
Nat. Hist. 
Case 27. Strontian salts ; carbonate of stron- 
tian^ also called strontianite, in prismatic and 
acicular crystals, which latter have sometimes 
been mistaken for arragonite.—Among the suU 
phates of strontian (celestine of Werner) the more 
remarkable specimens are, the splendid groups 
of limpid prismatic crystals from La Catolica 
in Sicily; the acicular variety in the hollows 
of compact sulphate of strontian, from Mont¬ 
martre ; the same in fissures of flint j the radiated 
and fibrous celestine, &c. 
The remainder of this case is occupied bysome 
other saline stony substances, viz, carbonate of 
magnesia, called also pure magnesia, and mag- , 
nesite. Borate of magnesia, or horacite, in sepa¬ 
rate crystals, and the same imbedded in gypsum; 
—hy dr argillite or wavellite, which may be consi¬ 
dered as a phosphate of alumina; azurite and 
blue spar (Werner’s lazulit and blauspath), which 
appear to be phosphates of alumina, magnesia, 
and silica ;— aluminite^ a subsulphate of alumina, i 
from Sussex, and from Halle in the territory of || 
Magdeburg, which was formerly mistaken by \i 
some for pure alumina, by others for a hydrate ic 
of alumina with mechanically admixed sulphate ,|j 
of lime ; it must not be confounded with alum- 
stone (alunite of French mineralogists), which. Hi 
according to Cordier, is a hydrate of alumina p 
with anhydrous sulphates of alumina and potassa. 
Fluate of soda and alumina, or cryolite (found 
only in West Greenland), pure^and intermixed | 
with 
