160 GOLD AMALGAM. 



Gold Amalgam, H. Schneider. AlSJ'ative 

 Amalgam of gold has been found in the 

 platinum district of Columbia, associated 

 with a platinum-ore, in small white globules 

 of the size of peas, and easily crushed by 

 pressure. 



Comp. (Au, Ag)2 HgS. 



Analysis, by Schneider : 



Mercury .... 57-40 



Gold 38-39 



Silver . . . . . 5"0 



100-79 



The amalgam of gold is also reported to 

 occur in California, especially in the neigh- 

 bourhood of Mariposa. 



GoNGiLYTE, Thoreld. An altered mine- 

 ral. Occurs massive, with a cleavage in 

 two directions. Colour yellow or yellowish- 

 brown. Subtranslucent. Lustre greasy. 

 Streak white. Fracture conchoidal. H. 4 to 

 5. S.G. 2-7. 



Comp. (Mg K)3 Si2 + 3A1 Si2 f 4iH, or 



2K si + 3fir Si + 3H (Nordenskiold). 



BB yields water, and fuses to a blebby 

 class. 



Locality. Yli Kit Kajarvi, in Finland. 



GosHENiTE, Shepard. Avariety of Beryl. 

 Occurs in large round transparent grains 

 and in short six-sided prisms, Avith their 

 alternate angles replaced by single planes. 

 Colour bluish-white, rarely rose-red. S.G. 

 2-35 to 2-76. 



Locality. Goshen, Massachusetts, U.S. 



Goshenite, when cut and polished, forms 

 a brilliant gem. 



GosLARiTE, Haidinger. Rhombic. Pri- 

 mary form a right rhombic prism: crystals 

 generally produced artificially. Usually 

 occurs massive, stalactitic, botrj^oidal, reni- 

 form and investing. Slightly efflorescent 

 on the surface. Colour greyish, reddish, 

 bluish, and greenish-white. Lustre vitre- 

 ous. Transparent or translucent. Taste 

 astringent, metallic and nauseous. Streak 

 white. Brittle. Fracture conchoidal. H. 2 

 to 2-5. S.G. 1-9 to 2-1, 



Fig. 218. 



Comp. Zn S + 6H = oxide of zinc 28-2, 

 sulphuric acid 27 9, water 43-9 = 100. 



GRAMENITE. 



Analysis, from Goslar, by Klaproth 



Sulphuric acid 

 Oxide of zinc . 



Oxide of iron 

 Oxide of manganese 

 Water . 



22-0 



27-5 



0-4 



0-7 



50-0 



1006 



In a matrass yields water. 



BB fusible with intumescence, gives off 

 sulphuric acid, and covers the charcoal with, 

 a white coating of oxide of zinc. 



Easily soluble in water. 



This salt, supposed to result from the de- 

 composition of Blende, with which it is fre- 

 quently associated, is principally found in 

 deserted galleries of old mines, in small 

 crystalline tufts composed of minute inter- 

 laced needles, usually yellow, but sometimes 

 coloured blue by sulphate of copper. 



Localities. — British. Holywell in Flintshire, 

 and occasionally in the Cornish mines; in 

 acicular crystals at the Tresavean and Tre- 

 thelian Mines, near St. Day. — Foreign. 

 Rammelsberg Mine in the Harz, and par- 

 ticularly where much Blende occurs. Spitz 

 in Austria. Schemnitz in Hungary. Salz- 

 burg. Fahlun and Sahlberg in Sweden, &c. 



This salt, in its manufactured state, is 

 extensively used in medicine and for d3-eing. 

 (See White Vitriol.) 



Name. From one of its localities, Goslar, 

 in the Harz. 



Brit. Mus., Case 55. 



GoTHiTE, Dana, Beudant, Greg 8j- Lett- 

 som. See Goethite. 



GoTTHAKDTiTE, Bammelsherg. See Du- 



FRENOYSITE. 



GouTTEs d'Eau. A name sometimes 

 given to pebbles of Topaz, in allusion to 

 their limpidity. The Brazilian variety, 

 when cut in facets like the diamond, closely 

 resembles it in lustre and brilliance. 



GouTTE DE Sang. Fine cochineal-red 

 or blood-red Spinelle. 



Gramenite, Krantz. A mineral analo- 

 gous to Pinguite and Nontronite, which has 

 resulted from the decomposition of some fels- 

 pathic rock, and by the substitution of per- 

 oxide of iron for alumina. It occurs in thiu 

 aggregated laminae of a fine grass-green 

 colour, like that of Pinguite. Lustre greasy. 

 H. 1. S.G. of dried mass 1-87. 



Comp. Silicate of peroxide of iron. 



Analysis, by Bergemann : 



Silica 38-39 



Alumina .... 6*87 

 Peroxide of iron . . . 25-46 

 Protoxide of iron . . . 2*80 



