212 H. A. Wheeler — A new variety of Zinc Sulphate. 



Art. XXIII. — Notes on Ferro- Goslarite, a new variety of 

 Zino Sulphate • by H. A. Wheeler. 



Associated with the sphalerite in a zinc-mine at Webb 

 City, Jasper Co., Mo., there occurs a new variety of goslarite, 

 or hydrous sulphate of zinc, that contains about 5 per cent of 

 ferrous sulphate. It appears as incrustations and in stalactitic 

 form on the wall of a large body of zinc-blende, with which 

 marcasite and galenite are associated. Its origin is due to the 

 oxidation and leaching of the zinc and iron sulphides, and their 

 subsequent crystallization as the solution slowly concentrated 

 by atmospheric evaporation. The occurrence of goslarite in 

 the drainage of the mines of that district is quite common, 

 according to Dr. W. P. Jenney, and where the seepage through 

 the ore-bodies is very slight, the normal white to colorless sul- 

 phate of zinc is occasionally found as an incrustation on the 

 sides of the mine ; but in this case, a double sulphate of zinc 

 and iron is found in the ratio of 4*9 FeS0 4 to 55*2 ZnS0 4 or 

 nearly as 1:11. Thus far it has been found in only one mine 

 and in very small amounts, which is hardly surprising in a 

 district that is usually seriously troubled with water, when the 

 ready solubility of the mineral is considered. 



The mineral occurs in mam miliary and stalactitic incrusta- 

 tions, with a prismatic, radiating structure. It is subtrans- 

 parent, and light yellow to brown in color. Luster, vitreous. 

 Hardness, 2*5. Brittle. Readily soluble in water, and has a 

 highly astringent taste. Readily loses its water on exposure 

 to the air, turning to an opaque, yellow powder. Fuses with 

 intumescence on charcoal, finally leaving an opaque, brown, 

 infusible mass that is feebly magnetic ; otherwise gives the 

 usual zinc and iron reactions. 



The analysis given below shows a very slight contamination 

 (0*8 per cent) from associated clayey matter, 



Zinc sulphate 55*2 per cent. 



Ferrous sulphate 4-9 " 



Water ... 39*0 " 



Silica 0-4 " 



Alumina 0-4 " 



Total 99-9 per cent. 



As the properties of the mineral correspond so closely to 

 those of goslarite, differing only, as far as studied, in the occur- 

 rence of ferrous sulphate with the variation to be expected 

 therefrom, I have given it the name of ferro-goslarite. I am 

 indebted to Mr. Arthur Thacher, E. M., for calling my atten- 

 tion to it, who first noticed its occurrence at Webb City and 

 placed some of the material at my disposal. 



