208 LAIT DE LUNE. 



Lait de Lune. Fibrous carbonate of 

 lime, when the filaments have become flat- 

 tened or broken by the action of infiltrating 

 water, or by drying in the open air. 



Lait de Montagne, Brochant. See 

 Agaric Mikekal. 



Lake Salt, Jameson. See Eock Salt. 



Lamellar Heavy Spar, Jameson. See 

 Barytes. 



Lampadite. a variety of Cupreous 

 Manganese. Amorphous. Colour bluish- 

 black. Lustre resinous. Structure some- 

 times reniform. H. above 2'5. 



BB infusible. 



Comp. Oxide of manganese 82, copper 

 13-5, silica 2-0 = 100. 



Locality. Tin mines of Schlackenwald, in 

 Bohemia. 



Name. After Lampadius, the Saxon me- 

 tallurgist. 



Lanarkite, Beudant ; Lanarkit, Hal- 

 dinger, v. Kobell. Oblique : primary form a 

 right rhombic prism. The crystals, which 

 are aggregated lengthways, are minute and 

 seldom distinct. Colour greenish - white, 

 yelloAvish-Avhite, or grey. Lustre adaman- 

 tine, on the cleavage-face pearly. Trans- 

 parent to translucent. Streak white. Sectile. 

 Thin lamina flexible, like Gypsum. H. 2 

 to 2-5. S.G. ^-^ to 7. 



Fi£?. 251. 



Comp. Sulphate and carbonate of lead- 

 oxide. Vh S + Pb C = sulphate of lead 53-15, 

 carbonate of lead 46-85 = 100. 

 Analysis, by Thomson : 



Carbonate of lead . . 46*04 

 Sulphate of lead . . . 53-96 



100-00 



BB on charcoal fuses to a globule, which 

 is white when cold, and is nearly reduced to 

 metallic lead. 



Effervesces slightly with nitric acid, in 

 which it is partially soluble, leaving a resi- 

 due of sulphate of lead oxide. 



Localities. — Scotch. Leadhills in Lanark- 

 shire, like fig. 251, in long slender crystals, 

 associated with Susannite and Caledonite.— 

 Foreign. Massive at Tanne' in Brunswick, 

 in the Harz, and in Siberia. Biberweier, 

 in the Tj^rol. 



Brit. Mus., Case 55. 



Lancasterite, Silliman. A mixture of 

 Brucite and Hydromagnesite, from Lan- 

 caster CO., Pennsylvania, U. S. 



LABIS LAZULL 



Brit. Mus., Case 47. 



Landscape Marble. See Cotham Mar- 

 ble. 



Lanthanite, Haidinger. Ehombic. Oc- 

 curs in small, thin, four-sided, tabular crys- 

 tals, with beveled edges. Generally fine 

 granular or earthy. Colour greyish-white, 

 vellowish, or pink. Lustre, dull or pearly. 

 "H. 2-5 to 3. S.G. 2-7. 



Comp. La C + 8H =lanthana 52-94, car- 

 bonic acid 21-11, water 2595 = 100. 



BB infusible; whitens, becomes opaque 

 and brownish-yellow. 

 Effervesces in acids. 



Localities. Bastniis, in Sweden, coating 

 Cerite. Lehigh co., Pennsylvania, in masses 

 composed of minute aggregated tables. The 

 Sandford Iron-ore bed, Moriah, Essex co., 

 New York, in thin scales or plates, varying 

 in colour from white to a delicate pink or 

 rose-tint, with Allanite. 



Lapis Ampelites of the ancients is the 

 Cannel Cpal of the moderns. 



Lapis Armenius, Kirwan. " Is Chalk or 

 Gypsum, impregnated with the blue calx 

 (carbonate) of copper." 



Lapis Lazuli. Cubical. Occurs in do- 

 decahedrons ; commonly massive, compact. 

 Cleavage dodecahedral, imperfect. Colour 

 rich Berlin- or azure-blue. Lustre faintly 

 glimmering. Usuallv translucent at the 

 edges. Opaque. H. 5-5. S.G. 2-38 to 2-45. 

 Comp. Silicate of soda, lime, and alu- 

 mina, with a sulphide probably of iron and 

 sodium. 



Analysis, by Varrentrapp : 



Silica 45*50 



Sulphuric acid . . . 5 89 

 Alumina .... 31-76 

 Lime ..... 3-52 



Soda 9-09 



Sulphur .... 0-95 

 Iron ..... 0-86 

 Chlorine .... 0-42 

 Water 0-12 



98-11 

 BB fuses with intense heat to a whitish 

 enamel. Colour not affected by a low red 

 heat ; effervesces and forms a colourless glass 

 Avith borax. 



Calcined, and reduced to powder, loses 

 colour, and gelatinises in muriatic acid. 



Lapis Lazuli is generally found in granite 

 or crystalline limestone, mixed with Fel- 

 spar, Quartz, and grains of Iron Pyrites. 

 It is brought from near Lake Baikal, in 

 Siberia ; also from Persia, China, and Bu- 



