392 TYROLITE. 



BB in borax, dissolves to a glass which 

 is brownish -yellow when hot, becomes green 

 when cooling, and when cold greenish- 

 yellow. 



Localities. A large felspar quarry at Helle, 

 at Nfesklll, 10 miles E. of Arendal, in Nor- 

 way, where it occurs abundantly, and oc- 

 casionally in crystals above two inches long. 

 The crystals are always attached at their 

 bases to plates of black Mica, and shoot out 

 and imbed themselves in the red Ortho- 

 clase. 



Tyrolite, Dana. Rhombic : crystalline 

 form unknown. Found in reniform masses, 

 Avith a radiating foliated structure, and a 

 drusy surface. Usually occurs in small 

 aggregations, and diverging fibrous groups, 

 of a pale green colour, and with a pearly 

 lustre. Colour verdigris-green to sky-blue. 

 Translucent. Lustre pearly. Streak paler 

 than the colour. Very sectile. Thin lamina 

 flexible. H. 1-5 to 2. S.G. 3-02 to 3 1. 



Comp. Cu^ As + 10 H + Ca C = arsenic acid 

 25-4, oxide of copper 43-8, water 19 8, car- 

 bonate of lime 11-0 = 100. 



Analysis, from Falkenstein, by v. Kohell ; 

 Arsenic acid . . . 25-01 



Oxide of copper . . . 43-88 



Water 17-46 



Carbonate of lime . . 13-65 



UMBER. 



100-00 



Soda 

 Water 



4-70 

 11-25 



BB decrepitates violently, and fuses to a 

 steel-grey globule. 



Soluble in acids, with evolution of carbonic 

 acid. 



Localities. Falkenstein, and other parts 

 of the Tyrol, whence the name Tyrolite. 

 Posing and Libethen, in Hungary. Nert- 

 (hinsk, in Siberia. Saalfeld, in Thuringia. 

 Riechelsdorf, in Hesse. Schneeberg, in the 

 Erzgebirge. Campiglia, in Italy. Asturia 

 and Linares, in Spain. 



u. 



UiGiTE, Heddle. Occurs in radiated 

 sheafy plates, somewhat resembling the 

 structure of a plumose Mica. Colourless, or 

 slightly yellowish. Lustre tremulous and 

 pearly. Brittle. H. 5-5. S.G. 2 284. 



Comp. Si5 (Ca4 Na) + Si2 Al + 9H. 



Analysis, by Heddle ; 



Silica 45-98 



Alumina . . . .21-93 

 Lime 16-15 



lOO'Ol 



BB fuses readily and quietly, with a 

 strong reaction of soda, to a white opaque 

 enamel. 



Locality. A quarry near Uig, in Skye, in 

 small nests in amygdaloid. 



Ulexite. The name applied by Dana, 

 in the 3rd edition of his Mineralogy, to 

 Borate of Lime, from a supposed difference 

 in composition from Hayesine. 



Named after Ulex, by whom it has been 

 analysed. 



Ullmannite, Frohell, Dana, Haidinger, 

 Nicol. Cubical: cubic cleavage perfect. 

 Generally occurs massive, with a granular 

 structure, or disseminated. Colour grey, in- 

 clining to tin- white or steel -grey. Opaque. 

 Lustre metallic. Brittle. Fracture uneven. 

 H. 5 to 5-5. S.G. 6-2 to 6-5. 



Comp. Ni (S, Sb, As)5 = nickel 26-9, sul- 

 phur 14-5, antimony (often partly replaced 

 by srsenic) 58-6 = 100. 

 "Analysis, from Siegen, by Ullmann t 



Antimony .... 47-56 



Nickel 26-10 



Arsenic .... 9'94 



Sulphur . . . .16-40 



100-00 



BB on charcoal partly volatilizes, with 

 fumes of sulphurous acid and antimony, 

 and ultimately fuses to a metallic globule, 

 which often gives a blue colour with borax. 



Soluble in concentrated nitric acid, with 

 a residue of sulphur, oxide of antimony, and 

 arsenious acid. 



Localities. 'J'he copper mines of Frens- 

 berg, Eisern, &c., in the Duchy of Nassau. 

 Landskrone, in Siegen, Prussia. H irzgerode 

 and Lobenstein, in Central Germany. 



Name. After Ullmann, the Hessian che- 

 mist and mineralogist 



3L P. G. Principal Floor, Wall- case 20. 



Ultramarine. The name given to the co- 

 lour prepared from pulverised Lapis Lazuli. 



Umber, Jameson, Werner. An earthy 

 variety of Limonite, used as a brown pig- 

 ment. It is found massive, in beds, in the 

 island of Cyprus. Its colour is between 

 liver-brown and dark yellowish-brown. It 

 is very soft, feels meagre, adheres slightly 

 to the tongue, and breaks with a large con- 

 choidal fracture. 



Analysis, by Klaproth : 



Peroxide of iron . . .48 

 Peroxide of manganese . . 20 



