MINERALOGY. 219 



cum which contained copper and zink : But, how- 

 ever, it is not long fince this femi-metal was difco- 

 vered to lie concealed in calamine, and that cala- 

 mine was its particular ore, and alfo a body of dif. 

 tinct qualities, prepared by nature, equal to that 

 which is got tolerably pure at the furnaces of 

 Gofllar, or that is imported from China, under 

 the name of Tutanague, Mr. Brandt removed a 

 great many doubts about the origin of zink, and the 

 metallic earth of the calamine, by having, in the 

 year 1734, a favourable opportunity of examining 

 the calamines, and different kinds of blendes, from 

 Rettwik in the province of Dalarne. He then 

 proved, in his hiftory of the femi-metals, that 

 blendes and calamines are ores of zink, and that 

 the clear alum-like vitriol, called Galitzenftein by 

 the Germans, (Sect, exxii.) was its vitriol. Soon 

 after, the blueifh grey zink ore was difcovered 

 by Mr. Von Swab at Bowallen, who in the year 

 1738 prepared calamine from it, and erected a work 

 for diftilling zir.k at large from it, at Wefterwiken 

 in Dalame ; which manufacture, however, after- 

 wards was laid afide for other intervening bufinefs. 

 Thus thefe firft difcoverers might perhaps have 

 given Meflleurs Pott and Margraff the opportu- 

 nity to write the hiftory of zink, then more 

 known to the world •, the former in his Treatife 

 Be Pjeudogakndi in the year 174I; and the lat- 

 ter in the Memoirs of the Academy of Berlin ; 

 though this notice is by no means intended to 

 prejuci'ce theie ingenious gentlemen of the ho- 

 nour thev merit, to have of themfelves had the 

 fame opinion, and purpofed the fame expert 

 ments. 



The zink ore from Ramelfberg in the Harfz, 

 is, like moft of the lead and copper ores from the 

 fame mines, of a very fine-grained texture > and 



if 



