Dii ofifu VditqueHnite, a rare ore of Chromium, in 



tli. United States. By J. Tobrey. 



Read April 27, 1835. 



A bout five years ago some specimens of lead ores were pre- 

 sented to me for examination by Professor Moore of Columbia 

 College. They were taken from a mine near the town of 

 Singsing, in the state of New- York, about one mile south of 

 the State Prison. The mine had been wrought for silver 

 nearly as long ago as the period of the American revolution, 

 and has occasionally been opened since that time. In 1^27 

 a company was formed for the purpose of working it, under 

 the impression that it contained a rich vein of silver. In 

 Cleaveland's mineralogy (ed. 2, p. 53'!) native silver is said 

 (on the authority of Col. Gibbs) to occur at Singsing, in a 

 very small vein. Mr. F. Cozzens obtained a specimen of the 

 native metal in that locality in the year 1825. The company 

 just alluded to, had theold shall cleared out, and also made, I 

 believe, a horizontal opening communicating with the shaft, 



the aide of the hill. A few barrels of ore were taken up, 



and the enterprise abandoned. The specimens that I exani- 



1 consisted of common galena, associated with copper 

 pyrites, crystallised carbonate of lead, malachite, and an 

 ochery looking Bubstance. The carbonate of lead was mostly in 



I] prismatic crystals which had b( me blackened through- 

 out, probably by the sulphuretted hydrogen disengaged from 



decomposing pyrites, but they still retained their high ada- 

 mantine lustre. Mostof the lumps of ore, contained much of 

 the substance, which I found consisted of clay, oxide 



