LAPIS LAZULI, 

 charia. Notwithstanding its deficiency of 

 lustre, and its not being susceptible of a 

 very exquisite polish, the beauty of its colour 

 has caused this stone to be used in jewelry, 

 generally for brooches and shirt-studs. It is 

 seldom employed for seals on account of its 

 comparative softness. The more richly co- 

 loured varieties are used for mosaics, and 

 are also made into vases and other costly 

 ornaments. 



When finely powered, and carefully wash- 

 ed, so as as to remove all foreign matters, 

 the product is the pigment called Ultra- 

 marine, so celebrated for its permanency 

 and the richness of its colour. The artificial 

 Ultramarine prepared by carefully heating 

 a mixture of clay, carbonate of soda and 

 sulphur, is said to be as durable and as rich 

 in tint as that manufactured from the native 

 stone, and can be sold for Ss. per lb. while 

 the latter costs five guineas an ounce. The 

 composition of the artificial colour, which is 

 now much used in the arts, according to 

 Varrentrapp, is as follows : 



Silica 45-60 



Sulphuric acid . • . . 3 83 

 Alumina .... 23-30 



Lime 0-02 



Soda . . . . . 21-47 



Potash 1*75 



Sulphur . . . .1-68 



Iron 163 



Chlorine .... trace 



= 98-78 

 In the Oriental account of the precious 

 minerals {Prinsep), it is said that " The 

 country of Badakshan abounds in moun- 

 tains, and contains several rivers. On the 

 Jihiin (Oxus) river, near where the Samar- 

 kand road crosses it, is the mine of Lapis 

 Lazuli. This mineral has different shapes ; 

 one like the egg of a hen, which is covered 

 with a thin, soft, and white stony coat, is 

 reckoned the best when pounded, — it needs 

 neither washing nor polishing ; the others 

 are without covering, and must be washed. 

 The method of washing is this: first to 

 pulverise it and afterwards to keep it wrapt 

 in silk cloth, besmeared all over with gum- 

 sandarach, which should be previously sof- 

 tened in very hot water, and then rubbed 

 over or kneaded with the hands ; it is kept 

 in the water for three days, until all the 

 foreign matter has been washed out." 



Lapis Lazuli, or Azure Stone, is supposed 

 to be the a-a.^(pu^o; of the ancients. Isidorus 

 says, " Sapphirus c^ruleus est cum pur- 

 pura, habens pulveres aureos sparsos," the 



' LASURITE. 209 



spangles of Iron Pyrites disseminated 

 through the stone bearing a great resem- 

 blance to gold. 



Brit. Mus., Case 55. 



M. P. G. Horse-shoe Case, Xos. 975 to 

 979. 



Lapis Mutabilis. An ancient name for 

 Hydrophane. 



Lapis Ollaris. See Potstone. 



Lapis Speculaejs, of the ancients, com- 

 monly signifies Mica, but sometimes Selenite. 

 Pliny states that many persons had made 

 beehives of Specular Stone that they might 

 see the bees at work within. 



Laederellite, Bechi, Dana. A very 

 light, white, and tasteless salt, which ap- 

 pears under the microscope to be composed 

 of minute, obhque, rectangular tables. 



Comp. Borate of ammonia, or NH^O, h"^ 



4H. 





Analysis, by Bechi : 

 Boracic acid . 

 Ammonia 

 Water . . . . 



. 68-56 

 . 12-73 



. 18-32 



99-61 

 Soluble in hot water, and is transformed 

 into a new crystallized salt, represented by 



the formula 4H4 b's + 9H. 



Locality. The lagoons of Tuscany. 



Name, After Count de Lardere!, inventor 

 of the successful method of obtaining Sasso- 

 lin from the water of the suffioni. 



M. P. G. Horse-shoe Case, No. 230. 



Lardite. a kind of Agalmatolite. 



Analysis, from Voigtsberg, in Saxony, by 

 Kersten : 



Silica 66-02 



Magnesia .... 31-94 

 Protoxide of iron , . . 0-81 



Soda 0-75 



Potash trace 



Water . . . . 0-20 



99-72 



Name. After Mons. Charles Lardi, of 

 Lausanne. 



Lasionite, Fuchs. A variety of Wavel- 

 lite, found in very slender silky fibres in 

 Jura limestone, at the mine of St. Jacques 

 near Amberg, in Bavaria, on Brown Iron 

 Ore. 



Brit. Mus., Case 57. 



Lasur, Haidinger, or Lasurxt, v. Kohell. 

 Blue carbonate of copper. See Chess y lite. 



Lasurite, Haidinqer. See Azurite. 



