GALLERY.] NATURAL HISTORY. *161 
produced by the decomposition of galena.— Oxide of bis¬ 
muth or bismuth-ochre, from Saxony and Bohemia.— Oxide 
of zinc or red zinc ore from New Jersey, and th e franklinite, 
composed of the oxides of zinc, manganese.— Black and 
yellow earthy cobalt , both called cobalt-ochre , which seem 
to be hydrates of the oxides of cobalt and manganese, 
frequently mixed with oxide of iron.— Oxide of uranium, or 
uran-ochre , and the hydrous protoxide of the same, called 
pitch-ore . 
Case 18. Oxide of tin or tin-stone, divided by Werner 
into common tin-stone and wood-tin: among the speci¬ 
mens of the former (chiefly from Cornwall, Saxony, and 
Bohemia) may be specified the greyish-white crystals re¬ 
sembling scheel-ore or tungstate of lime, the regular and 
macled crystals, the pebble-like and granular tin-stone 
(shoad-tin, stream-tin, grain-tin, &c.), the columbiferous 
oxide of tin from Finbo in Sweden; a variety of fibrous 
oxide or wood-tin, composed of radiated-fibrous small glo¬ 
bules, and marked with concentrically disposed brown and 
yellow colours, is called toad’s eye wood-tin* 
In the next Case begin the oxides of electro-negative 
bodies, and their various combinations. 
Case 19. Alumina and Aluminates. To the former 
belongs the corundum, comprehending the precious stones, 
commonly called oriental gems (the sapphire, ruby, orien¬ 
tal amethyst, oriental topaz, oriental emerald), of the crys¬ 
tallized forms of which the principal modifications are 
here deposited; and the common or imperfect corundum 
from Bengal, Mysore, China, the Carnatic (Werner’s dia¬ 
mond spar), Lapland, Piedmont, &c. As appendix to 
these are added, the jtbrolite, (bournonite of Lucas,) one 
of the concomitant substances of the common corundum of 
the Carnatic —the indianite of Bournon, being one of the 
matrices of the same corundum;—the emery, which owes its 
hardness and consequent usefulness in polishing to an ad¬ 
mixture of blue corundum.—The diaspore and the gibb- 
site: both hydrates of alumina.- 
Aluminate of magnesia —the spinel: among its varieties 
is the blue spinel of Aker in Siidermannia. The ceylon- 
ite or pleonaste, and the automolite (also called gahnite), 
from Fahlun in Sweden and from Franklin in New Jersey, 
are, the former an aluminate of protoxide of iron and mag- 
