MINERALS 



423 



three- fourths of the whole. This substance has prov- 

 ed to be of a metallic nature, by the coloured pre- 

 cipitates which it forms with prussiate of potash, 

 and with tincture of galls ; by the effects which zinc 

 produces when immersed in the acid solutions; and 

 by the colour which it communicates to phosphate 

 of ammonia, or rather to concrete phosphoric acid, 

 when melted with it/* The new metal retains oxy- 

 gen with great obstinacy, and is therefore very diffi- 

 cult of reduction. It is acidifiable; for the oxyd 

 reddens litmus paper, expels carbonic acid, and 

 forms combinations with the fixed alkalies. Still it 

 differs, in many particulars, from the other acidifi- 

 able metals of arsenic, timgstein, molybdsena and 

 chrome. And it is yet further removed from the 

 newly discovered metals of uranium, titanium, and 

 tellurium. 



No complete disoxydation of it has as yet been 

 effected. The pure metal, therefore, has pot been 

 seen, even by Mr. Hatchett himself. And if this 

 discerning experimenter had succeeded in freeing 

 the metal from its oxygen, the quantity he worked 

 upon was so very small, that it would have been 

 impossible to have gratified many of the curious by 

 presents. At this time it is not known what quan- 

 tity may exist in nature, nor to what economical 

 uses it may be applied.* 



The sulfihuret of zinc^ or blende, has been founds 

 in the Perkiomen lead mine: a small specimen of 

 it is in the collection of Dr. Seybert of Phila,« 

 delphia. 



