OF ARKANSAS. J49 



75.474 per eent. of carbonate of zinc, are equal to 48.95 per cent, of 

 oxide of zinc, or to 39.30 per cent, of metallic zinc. 



No. 2. Same as No. 1, impure. 

 Composition, dried at 230 deg. F: 



Clay, and silica 31.0G9 



Carbonate of zinc 51.111 



" " lime 8.114 



" " magnesia 4.417 



Peroxide of iron, with traces of alumina and 



manganese 4.800 



99.191 

 The air-dried mineral lost 1.29 per cent, of moisture at 230 deg. F. 

 51.111 per cent, of carbonate of zinc are equal to 33.149 per cent, of 

 oxide of zinc, or to 26.60 per cent, of metallic zinc. 



B. — Ore from the Bath mine. 



The prevailing ore at this locality is a massive, brownish-yellow, cellular 

 smithsonite; the cavities are clad out with botryoidal incrustations of 

 grayish-white smithsonite, and occasional buff-colored crystals of the same 

 mineral. The surface of the ore is covered with a thin crust of yellowish- 

 red clay. Several pieces of the ore were crushed, well mixed, and from 

 the mixture two samples taken for analysis, (No. 3 and No. 4). 



At this mine occurs also the light-colored, soft variety of carbonate of 

 zinc, partly amorphous, partly sub-crystalline, pieces of about a cubic 

 inch of which are cemented together by the dark brownish-gray or 

 brownish-yellow cellular smithsonite above described; the dark-gray cel- 

 lular masses often consist of concentric layers, the outer layers being gen- 

 erally of a much lighter color, and contain occasionally crystals of brown 

 blende. 



The dolomite containing the ore at this locality, abounds with small 

 veins of pearlspar, and with amygdaloidal cavities, sometimes an inch 

 wide and two and a half inches long, which are filled with crystals of 

 pearlspar and blende. 



No. 3. Brownish-yellow, cellular, smithsonite. 

 Composition, dried at 250 deg. F: 



Clay, and silica 8.831 



Carbonate of zinc 86.490 



" " lime 0.742 



" " magnesia trace 



