JOURNAL 



OF THE 



WASHINGTON ACADEMY OF SCIENCES 



Vol. VI DECEMBER 19, 1916 No. 21 



MINERALOGY.— Hopeite from the H. B. mine, Salmo, B. C. 

 T. L. Walker, Royal Ontario Museum of Mineralogy. 



The mineral hopeite, a hydrous zinc phosphate, occurs very 

 sparingly along with smithsonite, calamine, hydrozincite, spen- 

 cerite, hibbenite, and cerusite at the H. B. mine near Salmo, 

 B. C. It is remarkable that the ore as mined and shipped is 

 almost entirely free from sulphides even on the 300-foot level. 

 From this mine two new zinc phosphates, spencerite and hib- 

 benite, have been recently described. The phosphates occurred 

 in considerable quantity in a cave from which almost 100 tons 

 were sent to the smelter. Calamine and smithsonite appear to 

 be less prominent in this ore than the phosphates, which in 

 places occurred in very pure stalactitic masses weighing at least 

 ten pounds. In the stalactitic growths the central core is always 

 spencerite, while the outer zone is principally calamine. There 

 is often a solution zone between these two, and in these solu- 

 tion cavities small bright crystals of hopeite are found attached 

 to the spencerite by which they were at one time completely 

 enclosed. In general these crystals do not exceed 3 mm. in 

 length, although some attain a length of 1 cm. 



Chemical properties. As the amount available was insufficient 

 for a quantitative analysis the mineral was subjected to quali- 

 tative tests and found to respond in all respects to the reactions 

 of hopeite. Heated in the closed tube it yields water. In the 



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