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LVI. Descriptions mid Analyses of several Americaji Mine- 

 rals. By B. SiLLiMAN, Jun.t M.D.^ Professor of Che- 

 mistry applied to the Arts in Yale College^ and of Medical 

 Chemistry and Toxicology in Louisville Universityy Ken- 

 tucky^. 



nPHE results embodied in this article have been lately ob- 

 tained in the Analytical Laboratory of Yale College by 

 myself, or by my pupils under my immediate supervision and 

 direction. 



The researches upon the new and interesting species which 

 belong to the family of micas is not complete ; but as many 

 months must pass before I can again take up this investiga- 

 tion, it is deemed best to present the results already obtained, 

 that the attention of mineralogists may be directed to them. 

 I will present in a second memoir such further results as may 

 be determined by the analyses which will be carried forward 

 this winter on the same species. Enough has been done, it is 

 believed, to give definiteness and importance to the subject. 



I. Species of the Family Mica. 



This series of minerals, forming a new and very interesting 

 addition to the mica family, is found associated with the corun- 

 dum of Pennsylvania; and one or more of the species are 

 probably associated with corundum in every locality where 

 the latter is found. My attention was first called to these mine- 

 rals by receiving from Dr. J, L. Smith, now in Constantinople, 

 a small portion of a similar mineral, which he has called 

 Emerylite. The quantity of this mineral received (only 

 0"2 grm.) was too small to enable me to obtain more than 

 its general characters. As this mica was the means of calling 

 my attention to the others, I will repeat the results of Dr. 

 Smith, with such additional characters as were obtained here. 



Emerylite. 



This mineral is found associated with the emery from the 

 localities of Asia Minor. It is in brilliant micaceous scales, 

 brittle and inelastic. Colour, gray with a tinge of lilac; 

 laminae easily separable; hardness, 3 to 3*25; gravity not 

 satisfactorily determined on so small a quantity. Before the 

 blowpipe alone in forceps, exfoliates, whitens and emits a very 

 brilliant light, but does not fuse. In close tube, yields water, 

 which gave a feeble reaction for fluorine. Dissolves in borax 

 to a clear glass, and leaves a siliceous skeleton in salt of phos- 



• From Silliman's Journal for November 1849. 



