368 SUPEROXIDE OF LEAD. 



perfectly transparent when viewed in one 

 direction, but by reflected ligbt it appears 

 full of minute golden spangles, owing to 

 the presence of scales (or, according to 

 Scheerer, crystals), of oxide of iron, or 

 Gothite, disseminated through the mass. 

 The principal localities are, Lake Baikal, 

 in Siberia ; Archangel ; Tvedestrand, on the 

 Christiana-tiord, in Norway ; and Ceylon. 



Brit. Mus., Case 29. 



Superoxide of Lead, Dana. See 

 Plattnerite. 



Supersulphide of Lead, } See John- 



SUPERSULPHURETTED LeAD. j STONITE, 



Surturbrand. The name given in Ice- 

 land to the fibrous Brown Coal, or bitumi- 

 nous wood which is found in that country. 

 See Lignite and Brown Coal. 



SusANNiTE, Dana, Greg §■ Lettsom. 

 SuzANXiT, Haidinger. Hexagonal. Colour 

 pale green, yellow, gre}', dark brown. Trans- 

 parent to opaque. Lustre resinous, or pearly- 

 adamantine. Streak Avhite. H. 2'5. S.G. 



e-oo. 



Fig. 419/ 



Comp. Similar to Leadhillite, or Pb S + 



3PbC. 





Analysis, by Brooke t 





Sulphate of lead 

 Carbonate of lead . 



. . 27-5 

 . 72-5 



100-0 



Localities. — Scotch. In attached crystals 

 on the Susanna lode at Leadhilfs, in 

 Lanarkshire, associated with Lanarkite, 

 Leadhillite, and Cerussite. — Foreign. Mol- 

 dawa, in the Bannat, on Brown Iron-ore 

 and Galena. 



Brit. Mus., Case 55. 



Susannite may be distinguished from 

 Leadhillite, to which it otherwise bears a 

 close resemblance, by the rhombohedral 

 form of its crystals, and its higher specific 

 gravity. 



SvANBERGiTE, Igelstvom. Occurs mas- 

 sive. Colour pale red. H. 5. S.G. 3-3. 



Sulphuric acid 

 Phosphoric acid 



. 17-52 



. 17-80 



SYLVANITE. 

 Alumina .... 37-84 



Lime 6-00 



Protoxide of iron , . . 1-40 



Soda 12-84 



Water 6-80 



Chlorine .... trace 



100-00 



Locality. Wermland, in Sweden, with 

 Cyanite, Mica, Quartz, and Hematite. 



The name Svanbergite has also been ap- 

 plied by Shepard to Platiniridium. 



SwAOA. See Borax. 



Swamp-ore, Jameson. \ See Bog 



Savampy Iron-ore, Kirwan. j Iron-ore. 



Swimming Quartz, Bakewell. See Float- 

 stone. 



Swinestone, Kirwan. See Stinkstone. 



Syepoorite, Nicol, Brooke §- Miller. A 

 Sulphide of Cobalt, occurring in consider- 

 able quantities in grains or veins, in pri- 

 mary schist, mechanically mixed with 

 Magnetic Pyrites, at Saipoor, near Raj- 

 pootanah, in North Western India. It is of 

 a steel - grey colour, inclining to yellow. 

 S.G. 5-45. 



Comp. Co2 S. 



Analysis, by BFiddleton : 



Sulphur .... 35-36 

 Cobalt 64-64 



100-00 



It is used by Indian jewellers for impart- 

 ing a delicate rose colour to gold. 



Sylvan, Werner. Tellurium. 



Sylvanite, Kirwan. The name originally 

 given to Native Tellurium, from its being 

 first found in Transylvania. 



Sylvanite, Dana. Rhombic: primary 

 form a right rhombic prism. Generally 

 occurs in indistinct and minute circular 

 crystals, modified at the edges and angles, 

 and often grouped in rows, forming trian- 

 gular figures like letters. Cleavage in two 

 directions, nearly at right angles ; one very 



^ 



Fig. 420. 



Fig. 421. 



perfect. Colour steel-grey to tin-white, and 

 brass-yellow. Opaque. Lustre metallic; 

 sometimes with a slight tarnish. Streak like 

 the colour. Yields easily to the knife. Soft 



