186 Scientific Intelligefice.--^Mineralogy. 



MINEEALOGY. 



5. Okenite, a New Species of Zeolite. — Colours yellowish and 

 bluish white. Lustre glimmering, glistening, and pearly. Fi- 

 brous, sometimes passing into compact. Hardness, between that 

 of felspar and fluorspar. Specific gravity = 2.28 at 16° R. 

 Constititent parts. — Silica 5B.Q^ ; lime 26.59 ; water, with trace 

 of ammonia, 17-00 ; alumina with trace of iron, 0.53 = 99.76. 

 The essential constituent parts are then silica, lime and water, 

 which may be expressed by the following formula : 



C '^ S 8" H- 12 aq. ; or C 8^ + 2 aq. 



If we estimate the constituents according to this formula, there 

 results, 



Oxygen, . . 29.6 4 



74 1 



14.8 2 



99.99 



It was brought from Disco Island, in Greenland, and named by 

 Kobell in honour of Oken, the well known naturalist. 



6. On the Compact Garnet of Schwarzenstein or Zillerthal, 

 in the Tyrol. By Von Kobell.— Garnet generally occurs either 

 in regular crystals or in granular concretions ; seldom in a com- 

 pact form. A garnet of the latter description occurs at Schwar- 

 zenstein. Colour greyish and yellowish- white, which, in some 

 places, passes into pale green. Lustre resinous. Fracture un- 

 even, imperfect conchoidal, or splintery. Translucent on the 

 edges. Specific gravity = 3.86 at 15|° R. Melts easily and 

 quietly before the blowpipe, and agrees with calcareous garnet 

 in its relation to fluxes, and in the humid way. Constituent 



99.35 



