263 New Specific Gravities of Minerals. 
Art. IX.—Breithaupt’s new Specific Gravities of Minerals ; by 
r. Lewis Feucutwancer, of New York. 
Tue indefatigable Prof. Breithaupt, of Freiberg, in whom mine- 
ralogy has its most zealous cultivator, and to whom the scientific 
world owes great discoveries for the last fifteen years, has lately re- 
examined a great number of minerals the specific gravity of which 
has in many instances. not yet been known at all, and in some instan- 
ces could not from circumstances be given correctly, and they are: 
1. 2.629, Common siliceous schist, lydian stone from Erzge- 
birge, Saxony. 
2. 2.761, Bitterspar, from Iringen. 
8. 2.717, Eugnostic calcareous spar, from Rotluf near Chem- 
nitz, Saxony. 
4. 4.793, Tron ore, Imenite, from the Uralian mountains, ac- 
&.. 4.794, companying the zircon in granite, black and con- 
choidal. 
6. 2.330, Comptonite, from Vesuvius. 
7. 2.361, The same, from Bohemia. 
8. 3.002, Small and fine granular batrachite from Tyrol. 
9. 22.109, Native iridium in grains, lately received from Uralian 
Mountains. 5 
10. 17.840, Two pretty large and pure grains of iridosmin, from 
Uralian Mountains. 
11. 3.185, Fluorspar-crystal, from Switzerland. 
12. 1.989, Brown sulphur, from Croatia. 
38. 2.724, Scapolite, from Arendal, Norway, fresh greenish grey 
and hardness 7. 
14. 2.241, : Opal, Werner’s semi-opal from Freiberg, the hardest 
2.250. known varieties. 
= aoe. Stilpnosiderite, from the Voigtland. 
18. 2.700, Meroxene calcareous spar, (spar R.=105° 11’,) from 
Tharaud, Saxon 
19. 7.198, Calamine leadspar, diebice phosphate of lead,) from 
Zschoppau, Saxony 
20. 3.388, Transparent erystal of epidote, from Piedmont. 
21. 3.351, Pyroxene, which deserves more investi gation, passing 
generally for acolophonite from Arendal, Norway- 
22. 3.437, Retinophane pyroxene, the common. colophonite, 
rom Arendal 
