RE-EXAMINATION OF AMERICAN MINERALS * 



In the investigations which will be detailed we have en- 

 deavored to clear up the doubts due to imperfect analyses and 

 descriptions that exist respecting several American minerals. 

 Every care has been taken to procure the best specimens, and 

 our results have been tested by several analyses of each. We 

 are under obligations to several mineralogists of this country 

 who have placed their cabinets at our disposal for this inves- 

 tigation, and among those to whom we are more specially 

 indebted we take pleasure in mentioning Messrs. L. White 

 Williams and W. W. Jeffries, of Westchester, Pa.; T. F. Seal, 

 of Philadelphia; and Mr. Theo. S. Gold, of West Cornwall, Ct. 



1. Emerylite identical with Margarite. 



Emery lite was originally found by one of us on the emery 

 of Asia Minor, and also on the same mineral coming from the 

 Grecian Archipelago, Siberia, and China; it was subsequently 

 traced by Prof. Silliman, jr., in connection with the corundum 

 occurring in various parts of this country. Its constant occur- 

 rence with emery and corundum (forming one of the minerals 

 of elimination in their formation) suggested the name emery- 

 lite as most appropriate, its composition having been found to 

 be different from that of any known mineral. 



It was justly considered an interesting species, on account 

 of its accompanying the various forms of corundum wherever 

 observed ; and it may be safely said that no mineral has been 

 proved to be as widely distributed in so short a time after the 

 first announcement of its connection with the emery of Asia 



*In the first half of this re-examination I was assisted "by my friend, 

 George J. Brush. 



