OF ZINC. 355 



(1.) Anhydrous carbonate. It occurs crystal- 

 lized in very small obtuse rhomboids. It has a 

 yellowish white colour, and a specific gravity of 

 4*334 ; it dissolves with effervescence in sulphu- 

 ric acid, and is composed of 



1 atom carbonic acid 2' 75 



1 atom oxide of zinc 5*25 



8 



Carbonate of zinc, obtained by precipitating sul- 

 phate of zinc by carbonate of soda, washing the 

 precipitate, and drying it at 212, is likewise an- 

 hydrous. 



(2.) Hydrous carbonate of zinc. It has not 

 yet been met with in crystals ; but it has a white 

 colour, or yellowish white colour, and is most 

 commonly stalactical. Its specific gravity is 

 3*584 ; it dissolves with effervescence in sulphu- 

 ric acid, and does not gelatinize with acids. Its 

 constituents are 



1 atom carbonic acid . 2-?5 

 1 atom oxide of zinc . 5*25 

 1 atom water . . 1-125 



9-125 



4. Phosphate of zinc. This salt may be ob- Phosphate, 

 rained by mixing together solutions of sulphate 

 of zinc and phosphate of soda in the atomic 

 proportions. The phosphate of zinc immediate- 

 ly appears in white flocks, which are soon depo- 

 sited in a pulverulent form. When dried in the 



Z2 



