354 SPEERKTES. 



Salisbury Craig, near Edinburgh. Dunkeld 

 and Ben More, Perthshire. Hilleswick, in 

 Mainland, one of the Shetlands. — Irish. 

 Bennevenagh, in greenstone, associated with 

 Stilbite. Kerry Head. — Foreign. Island of 

 Elba, in very fine crystals, frequently pre- 

 senting beautiful tarnish -colours, and occur- 

 ring in druses of the massive variety. 

 Arendal, in Norway. Katherineuburg and 

 Nijni-Taguilsk, in the Ural. Langbans- 

 hyttan, in Sweden. St. Gotthard. Fra- 

 mont, in the Vosges. Tilkerode, in the 

 Harz. Capas, in Brazil, associated with 

 Quartz. Fowler, Hermon, Rossie Iron 

 Mines, St. Lawrence co. ; and at Antwerp, 

 Jefferson co., in New York. Canada: in 

 the Huronian series ; also at the Bruce 

 Mine, on the N, shore of Lake Huron, in 

 Huronian Limestone. In the volcanic rocks 

 of Auvergne, Vesuvius (especially on Monte 

 Somma), Etna, the Lipari Islands (especially 

 Stromboli), Island of Ascension, &c. 

 Brit. Mus., Case 14. 



M. P. G. Principal Floor, Case 48 

 (British) ; Upper Gallery, Table-case A, in 

 Recess 4, Nos. 72 to 74. 



Specular Iron constitutes a highly valu- 

 able ore, which has been extensively worked 

 in the Isle of Elba for upwards of 2000 

 years. It occurs in large beds or veins, 

 chiefly in crystalline rocks, and is also met 

 with among the ejected lavas of Vesuvius, 

 and other volcanos. 



It has lately been proved by Rammels- 

 berg that some of the specimens from. Elba 

 contain titanic acid, and that all of them 

 (as well as the Specular Iron from Vesuvius), 

 invariably contain protoxide of iron, and an 

 essential per centage of magnesia. 

 Brit. Mus., Case 15. 



M. P. G. Principal Floor, Wall-cases 18 

 (Foreign) ; 41 (Ascension), 

 Speekkies. See Spear Pyrites. 

 Speiskobalt, Werner. See Sbialtine. 

 Speiskobold, Werner; or Speissko- 

 BALT, Hausmann, Tin-white Cobalt. See 

 Smaltine. 

 Spelter. A commercial name for Zinc. 

 Spessartine, Beudant. A Manganese- 

 alumina Garnet, occuring in dodecahedral 

 crystals and massive. Colour deep hyacinth 

 or brownish-red. Slightl}' translucent at 

 the edges. Fracture imperfect-conchoidal, 

 and presenting a vitreous lustre. H. 7 to 

 7-5. S.G. 3-7 to 4-4. 



Comp. (Mn5-fAl)Si. 



Analysis, from Miask, by Lissenko. S.G. 



Silica . 



36-30 



SPH/EROSTILBITE. 

 Alumina .... 17*48 

 Protoxide of manganese . 30'60 

 Protoxide of iron . . 14-32 

 Lime 0-51 



99-21 

 BB alone, fuses : with soda, on platinum 

 foil, exhibits a decided green colour, indica- 

 tive of the presence of manganese. 



Localities. Aschaffenburg, in Franconia, 

 in granite. Finbo and Brodbo, near Fah- 

 lun, in Sweden. Haddam, in Connecticut, 

 in large brittle trapezohedrons, often two 

 inches through, with Chrysoberyl. 



Name. After that of the locality, Spessart, 

 in Germany. 



Sph^rolite. See Sph.erulitk. 

 Sph^erosiuerite, or Spharosiderite, 

 Hausmann. A spheroidal and radiated 

 variety of Sparry Iron (C/ialybite), found in 

 greenstone, at Hanau, in Western Germany, 

 and in the circle of Jaslo, in Austrian Ga- 

 licia. 



Analysis, from Steinheim, near Hanau, by 

 Stromeyer : 



Carbonic acid . . . 38-04 

 Protoxide of iron . . . 59-G3 

 Protoxide of manganese . 1-89 

 Lime 0-20 



99-76 

 Many kinds of Brown Iron Ore appear to 

 be formed by the deposition of hydrated per- 

 oxide of iron from water containing carbo- 

 nate of iron in solution, as it issues out of 

 the earth and evaporates in the air. If this 

 water give off its carbonic acid out of con- 

 tact of air, it deposits monocarbonate 

 of protoxide of iron, in the form of Sphagro- 

 siderite. — (Bischof, quoted b}' L. (jmelin, 

 vol. V. p. 196.) 



Brit. Mus., Case 48. 



Sph.erostilbite, Beudant. A variety of 

 Stilbite, occurring in minute crystals upon 

 delicate radiated tufts of Mesolite, which 

 cause it to assume a globular form. The 

 crystals, which give it the appearance of 

 having a radiated structure, are flexible, 

 and the surfaces of the globules may be 

 scratched with the nail. H. above 3. S.G. 

 231. 

 Analysis, from Skye, by Heddle : 



Silica 56-54 



Alumina . . . .16-43 



Lime 8-90 



Soda 0-46 



Water 17-05 



99-38 



