206 DESCRIPTIONS OF MINERALS. 
Bledite. A hydrous sodium-magnesium sulphate ; from the salt 
mines of Ischl, and near Mendoza. 
Leweite. A hydrous sodium magesium sulphate ; from Ischl. Con- 
tains more sulphur trioxide than Bleedite. 
Boracite.—Magnesium Borate. 
Isometric. Cleavage octahedral; but only in traces. 
1. Usual in cubes with only Be 
alternate angles replaced ; 
having all replaced, but four 
of them different from the 
other four. ‘The crystals are 
translucent and seldom more 
than a quarter of an inch 
through. Also massive. Color white or grayish ; sometimes 
yellowish or greenish. Lustre vitreous. H. = when in 
crystals, but softer when massive. G.=2:97. Becomes 
electric when heated, the opposite angles of the cube be- 
coming of opposite poles. 
Composition. Mg, O,, Bs +4Mg Cl,= Boron trioxide 62:0, 
magnesia 31:0, chlorine 7°0=100. B.B. fuses easily with in- 
tumescence coloring the flame green. The fused globule 
becomes crystalline on cooling. Dissolves in hydrochloric 
acid, and moistened with cobalt nitrate turns pink on igni- 
tion. 
Diff. Distinguished readily by its form, high hardness, 
and pyro-electric properties. 
Obs. Boracite is found only with gypsum and common 
salt. It occurs near Luneberg in Lower Saxony, and near 
Kiel in the adjoining duchy of Holstein, also at Stassfurth, 
Prussia. 
Rhodizite. Resembles boracite in its crystals, but tinges the blow- 
pipe flame deep red. It is supposed to be a lime-boracite. Occurs 
with the red tourmaline of Siberia. Ludwigite. A magnesium-iron 
borate ; fibrous and dark green to black. 
Szuibely yite. A hydreus magnesium borate, from Southeastern 
Hungary 
Warwickite. In rhombic prisms of 93° to 94°, hair-brown to black 
with sometimes a copper-red tinge. A magnesium-titanium borate ; 
from granular limestone of Edenville, N. Y. 
Sussexite. A hydrous magnesium-manganese borate. Fibrous and 
pearly. G—3-42. from Mine Hill Franklin Furnace, Sussex Co., N. J. 
Nitromagnesite. Occursin white deliquescent efilorescences, having 
a bitter taste, associated with calcium nitrate, in limestone caverns. It 
is used, like its associate, in the manufacture of saltpetre. 
Wagnerite. A magnesium fluo-phosphate, occurring in yellowish cr 

