THE ALKALINE AND BOB AC 10 LAKES OF CALIFOBNIA. 181 



k aline taste. The portion insoluble in water ef- 

 fervesces on being attacked by hydrochloric acid, 

 and contains silica, alumina, lime, ferrous oxide, 

 and magnesia. Similar deposits containing borax 

 exist in Panamit and Death's Valley, in Lower Ne- 

 vada ; but these desolate districts have not as yet 

 received so careful an examination as they deserve. 



About twenty miles west of San Bernardino 

 is the so-called " Cane Spring District," where 

 ulexite or boronatrocalcite is found, over an area 

 about ten miles in width by fifteen in length. The 

 surface of the ground is covered by efflorescent 

 salts, commonly known as " alkali," beneath 

 which the borax salts (chiefly ulexite) are found 

 at a depth of only a few inches. 



At Hot Springs, in the northwestern portion 

 of the State of Nevada, at a height of 4,500 feet 

 above the level of the sea, and where the water 

 issuing from the ground has a temperature of 

 about 190° Fahr., there are deposits of boronatro- 

 calcite, extending over considerable areas. Here, 

 as far as the eye can reach, nothing is seen but 

 barren mountains, formed of a black, porous 

 lava ; while the valleys are covered by an efflo- 

 rescence of a mixture of common salt and sul- 

 phate and carbonate of sodium. In other cases 

 the sands of these mountain-valleys contain de- 

 posits of more or less pure boronatrocalcite. 



Geysers and hot springs are numerous in the 

 whole of this district, and from the number of ex- 

 tinct geyser-vents still visible they were, probablv, 

 at one time much more numerous than at present. 



The analysis of an average sample of the 

 boracic material from Nevada afforded Mr. Loew 

 the following results : 



Boronatrocalcite 22.13 



Chloride of ■sodium 2.^0 



Sulphate of sodium •>. 62 



Sulphate of calcium 6.17 



Carbonate of calcium 3_o{ 



Carbonate of magnesium 79 



Clay .' .' 19.70 



Quartzose sand 26.08 



Water \ 15^4 



Traces of potash, iodine, and loss 1.71 



100.00 1 

 1 Monitewr Scienlifique, 1S76, p. 1230. 



The purification of crude borax {lineal) is ef- 

 fected by a simple recrystallization, but the prep- 

 aration of marketable borax from boronatrocal- 

 cite is attended with considerable difficulty, more 

 particularly as the appliances available in the re- 

 mote deserts in which it occurs are of the most 

 primitive and limited description. 



When boronatrocalcite is moderately pure it 

 is first ground and subsequently dissolved in wa- 

 ter, with the addition of an amount of carbonate 

 of sodium sufficient to effect the decomposition 

 of the calcic carbonate present. 



The solution is subsequently heated, and the 

 carbonate of calcium allowed to subside, when 

 the liquor is drawn off, and, after concentration, 

 borax is obtained by crystallization. 



Unfortunately, this mineral often contains 

 notable quantities of gypsum, which transforms 

 an equivalent amount of carbonate of sodium into 

 Glauber salt, a relatively valueless product. This 

 salt is also frequently present in the material 

 operated upon, and thus materially adds to the 

 difficulty of treatment. In order to avoid these 

 difficulties, it has been proposed to treat native 

 boronatrocalcite with sufficient sulphuric acid to 

 transform the whole of the carbonate of calcium 

 into gypsum, and to liberate boric acid to be 

 subsequently saturated by carbonate of sodium. 

 Boronatrocalcite has also been treated with ex- 

 cess of hydrochloric acid, in order to obtain crys- 

 tallized boric acid, but neither of these process- 

 es has hitherto afforded satisfactory commercial 

 results. 



The comparatively recent discovery of large 

 quantities of this substance in Nevada will, no 

 doubt, eventually, to some extent, affect the Tus- 

 can producers of boric acid ; but the fact that 

 crude boronatrocalcite varies considerably in its 

 composition, and that it is found in situations in 

 which its local treatment would be almost impos- 

 sible, has hitherto prevented this mineral from 

 being extensively employed as a source of com- 

 mercial borax. — Popular Science Review. 



