ON THE AUTOMALITE. 249 



On a new locality of the Automalite. By Lardneu 

 Vanuxem. Head July 16, 1822. 



Among the many various and interesting minerals 

 which are presented to us by the new and prolific 

 locality of Franklin, in Sussex county, New Jersey, 

 is the Automalite, or Spinelle Zincifere of the Abbe 

 Haiiy, a mineral hitherto confined to Uto in Sweden, 

 and which is there found imbedded in talcous rocks. 



The Automalite of Franklin was discovered in 

 August 1821, by William H. Keating, Esq. and 

 myself. It occurs in crystals presenting its primitive 

 form, the regular octahedron, with all its edges 

 emarginated ; in size it varies from microscopic to 

 two-thirds of an inch in leugth. Its colour is of a 

 beautiful dark green, usually translucent and some- 

 times almost transparent. With borax it fuses be- 

 fore the blowpipe, forming a yellow glass when hot, 

 which on cooling changes to a beautiful and perma- 

 nent violet ; this colour is due to the oxide of man- 

 ganese, which gives to the mineral its green colour. 

 This action with the blowpipe is analagous to that 

 of the Swedish Automalite. Its hardness is the same 

 as that of the Swedish. Instead of being accom- 

 panied by talc as in Sweden, it is found at Frank- 

 lin with quartz, feldspar, Jeffersonite, silico cal- 

 careous oxide of titanium, &c. 



In order to ascertain that this mineral was really 

 a Zinciferous Spinelle, it was chemically examined 

 in the following manner : the quantity operated on 



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