EXTRA-LIMITAL SPECIES. 455 



pipe, willi the evolution of arsenicnl vapours. Composed of ursciiic GS.50, cobalt 9.60, iron 

 9.70, copper 1.00, yulpliur 7.00. 



Chatham, Connecticut, associated with arsenical iron pyrites and copper nickel. 



TEPHROri'E. 



Toj)hroilc, L-'tmhnri!. 



Colour ash-grey, liver-brown to black. Massive and compact. Ln.strc adamantine. Hard- 

 ness 5.0 to 6.0. S]). gr. 4.10 to 4.12. Before ihc blowpipe, fuses into a black slag. 



Sparta, New-Jersey, with franklinite. It is supposed by Shepard to be a variety of 

 troostite. 



TIN ORE. 



Oxit'.c of Tin. C'l'-iivd'im!, 



Colour white, grey, yellow, red, brown and black. Streak grey or brown. Crystallized 

 and massive. Primary an octahedron with a square base. Ijustre adamantine. Semi-trans- 

 parent to transparent. Hardness 6.0 to 7.0. Sp. gr. 6.51 to 7. 10. On charcoal, before the 

 blowpipe, it is reduced to the metallic state. Composed of oxide of tin 95.00, o.xide of iron 

 5.00. 



Goslien, Massachusetts ; and in considerable quantity in Jackson, New-Hampshire. 



TOl^AZ. 



Colour various shades of yellow, green, blue or red. Streak white. Crystallized and 

 massive. Primary a right rhombic prism. Jf on 31' 12P 22'. Lustre vitreous. Translu- 

 cent to transparent. Hardness 8.0. Sp. gr. 3.49 to 3.56. Scarcely fusible before the 

 blowpipe. Composed of alumina 57.45, silica 34.24, fluoric acid 7.75. 



Middletown and Trumbull, Connecticut. A specimen from the vicinity of Carmcl in Put- 

 nam county, N. Y., closely resembles topaz ; but the crystals are loo small and imperfect to 

 determine positively. 



TRIPLITE. 



rliospliatc' 111' M.Tiig.incse. Clam la ml. 



Colour blackish brown. Massive. Lustre resinous, inclining to adamantine. Translucent 

 on the edges to opaque. Brittle. Hardness 5.0 to 5.5. Sp. gr. 3.43 to 3.7S. Melts be- 

 fore the blowpipe into a black scoria. Composed of oxide of iron 31 .00, oxide of manganese 

 42.00, phosphoric acid 27.00. 



Washington, Connecticut; Sterling, Massachusetts. 



