352 SOFT COAL. 



3'ellowish, greeuish, blue. Translucent. 

 Lustre vitreous. Yields with difficulty to 

 the knife. Fracture conchoidal. H. 5-5 to 

 6. S.G. 2-26 to 2-37. 



Comp. Na3 Si +3'^1 Si + Na CI = silica 

 37-2, alumina 31-7, soda 19'1, sodium 4-7, 

 chlorine 7-3 = 100. 

 Analysis, from Greenland, by J^keberg : 



Silica 36-60 



Alumina .... 32-00 



Soda 25-00 



Peroxide of iron . . 0-15 



Muriatic acid . . . 6-75 



S9-90 



JBB fuses easily, sometimes tranquilly, 

 sometimes swelling up and forming a blis- 

 tered glass. 



With muriatic acid, readily yields a sili- 

 ceous jelly. 



Localities. — The Kangerdluarsukfiord, W. 

 Greenland, of a green colour. Ilmen Moun- 

 tains, in the Ural. Near Brevig, in Norway, 

 The Kaiserstuhl, in the Briesgau, massive, of 

 a grey colour,in trap rock. Vesuvius, in large 

 white dodecaliedral crystals. Val di Noto, 

 in Sicily. Riiden, near Laach. United 

 States: at Licli field, Maine, in a granitic 

 ^•ock ; Salem, Massachusetts, in a vein six 

 feet wide, in syenitic porphyry. 



Name. From soda, and a/^o?, stone, in al- 

 lusion to the soda it contains. 



Brit. Mus., Case 31. 



Soft Coal. See Caking Coal. 



SoiMONiTE. See Corundum. 



Solfatarite, Shepard. Soda alum. The 

 name is in allusion to its occurrence at the 

 Solfatara, near Naples. 



SoMERViLLiTE, Brooke, Phillips. A va- 

 riety of Mellilite, of a dull yellow colour, 

 occurring among the older scoria of Vesu- 

 vius, associated with black Mica, &c. It 

 may be distinguished from Idocrase by 

 decrepitating before the blowpipe, and by 

 yielding alone, a /jf/'ey globule. It was named 

 by Brooke after Dr. Somerville, from whom 

 he obtained his specimens. 



Brit. Mus., Case 35. 



SoMMiT, Karsteji. \ A name for Nephe- 



SoM:snTE, Phillips, j line, in allusion to its 

 occurrence at Monte Somma, the ancient 

 crater of Vesuvius. 



SONNENSTEIN. See SUNSTONE. 



Sooty Silver ore, Kirwan. See Silver 



BLACK. 



Sorbawalite, Nordenskiold. A variety 

 of Wichtyne, resembling Pit-coal in appear- 

 ance, found in greyish or bluish-black 



SPANIOLITE. 



opaque masses, without any apparent cleav- 

 age. Lustre vitreous. Streak liver-brown. 

 Brittle. Fracture conchoidal. H. 2-5. S.G. 

 2-53 to 2-58. 



Co7np. ( Mg Fe)3 Si + Al Si. 



Analysis, by Nordensldold ; 



Silica . . . . . 49-40 



Alumina .... 13-80 



Protoxide of iron . . . 18-17 



Magnesia .... 10-67 



Phosphoric acid . . . 2-68 



Water . . . . . 4-38 



99-10 



BB alone fuses with difficulty to a black- 

 is?! globule. With borax forms a green 

 glass. 



Partially soluble in muriatic acid, and 

 turns red on exposure to the air. 



Localities. Near Sordawala (whence the 

 name) in Finland, forming thin layers in 

 trap rock. Bodenmais, in Bavaria. 



Brit. Mus., Case 31. 



Soude Boratee, Haily. See Borax. 



SouDE Carbonatee, Haiiy. See Na- 

 tron. 



Soude Carbonates Prismatique. Du- 

 frenoy. See Thermonatrite. 



Soude Muriatee, Haily. Common salt. 

 See Rock Salt, 



Soude Nitratee, Haiiy. See Nitra- 

 tine. 



Soude Sulfates, Haiiy. See Glauber 

 Salt. 



SouFRE, Haily. See Sulphur. 



Spadaite, v. Kohell. Massive. Colour 

 red, inclining to flesh-red. Translucent. 

 Lustre resinous. Streak white. Sectile. 

 Fracture imperfect-conchoidal. H. 2'5. 



Comp. MgS SU + 4H, or 4Mg Si -f Mg H. 



Analysis, by v, Kohell ; 



Silica . : . . . 56-00 

 Magnesia .... 30-67 

 Protoxide of iron . . . 0-66 

 Alumina .... 0-66 

 Water 11-34 



99-33 



BB fuses to a glassy enamel. 



Soluble in concentrated muriatic acid, 

 the silica readily forming a jelh^ 



Locality. Capo di Bove, near Rome. 



Name. After Signor de Medici Spada. 



Brit. Mus., Case 26. 



Spaniolitis. The name given by v. Ko- 

 hell to the varieties of Grey Copper con- 

 taining quicksilver. S.G. 5-107. 



