LAPIS LAZULI AMBER AND MALICHITE. 



LAPIS LAZULL 



This stone was the sapphire of the 

 Greeks, Romans and Hebrew Scrip- 

 tures. Pliny Hkened it to the blue 

 sky adorned with stars. Large 

 quantities of worked pieces of it 

 are found in early Egyptian tombs, 

 and the Chinese have long held it in high 

 esteem. Marco Polo visited Asiatic 

 mines of the mineral in 1271 A. D., and 

 these had doubtless been worked for a 

 long time previous. Besides its value as 

 a stone it was in former times used as a 

 blue pigment, giving the ultramarine 

 blue. In modern times not only has the 

 esteem in which the stone is held for or- 

 namental purposes declined but the min- 

 eral can be artificially made so as to give 

 the desired blue color for paints and thus 

 the use of the natural lapis lazuli has 

 greatly diminished. It is still however 

 carved to make vases, small dishes, 

 brooches and ring stones and is used tO' a 

 considerable extent for mosaic work. 

 When, also, pieces of sufficient size and 

 of a uniform color can be found, large 

 carved objects may be made which com- 

 mand a high price. 



The stone known as lapis lazuH as it 

 occurs in nature is not a single mineral 

 but a mixture of several, among which 

 are calcite, pyrite and pyroxene. From 

 these however it is possible to separate a 

 mineral of uniform composition some- 

 times crystallized in dodecahedrons 

 which is probably the essential ingred- 

 ient of the stone. This mineral is known 

 as lazulite and in composition is a sili- 

 cate of soda and alumina with a small 

 quantity of sodium sulphide. It is by 

 making a substance of this composition 

 that the artificial ultramarine is pro- 

 duced. The artificial is said to be as 

 good as the natural for a pigment and 

 can be produced for a three-hundredth 

 part of the cost. The natural lapis lazuli 

 has a hardness of 5 1-2 and a specific 



gravity about like that of quartz. It is 

 quite opaque. In color it is blue, vary- 

 ing from the prized ultramarine to paler, 

 and at times is of a greenish shade. 

 It is said the pale colored portions can t)e 

 turned darker by heating to a red heat. 

 When the variety from Chile is heated 

 in the dark it emits a phosphorescent 

 green light. The stone in Nature is of- 

 ten flecked with white calcite. Portions 

 so affected are not considered as valu- 

 able as the uniform blue. Grains of py- 

 rite are also usually scattered through the 

 stone giving the *'starry" effect referred 

 to by Pliny. 



Lapis lazuli usually occurs in lime- 

 stone but in connection with granite so 

 that it seems to be a product of the erup- 

 tion of the granite through the lime- 

 stone. The lapis lazuli of best quality 

 comes from Asia, the mines being at 

 Badakschan in the northeastern part of 

 Afghanistan on the Oxus river. The 

 miining is done by building great fires on 

 the rocks and throwing water on them to 

 break them. The yield at present is 

 small, not over 1,500 pounds a year be- 

 ing obtained. The lapis lazuli from 

 these mines is distributed all over Asia, 

 going chiefly to China and Russia. The 

 price realized is said to be from $50 to 

 $75 per pound. Lapis lazuli of poorer 

 quality comes from a region at the 

 western end of Lake Baikal in Siberia. 

 The only other important locality is in the 

 Andes Mts. of Chile near the boundary 

 of the Argentine Republic. This ma- 

 terial is not much used at the present 

 time on account of its poor quality but 

 it was employed by the Incas for decor- 

 ative purposes. One mass 24x12x8 in., 

 doubtless from this locality is now in the 

 Field Columbian Museum, and was found 

 in a Peruvian grave. It is one of the 

 largest masses of lapis lazuli known. 



The walls of a palace at Zarskoe-Selo, 

 Russia, built by order of Catherine II 

 are entirely lined with slabs of lapis 



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