66 



H. G. Hanks — Hanksite in California. 



m 



m 



thirty in all. About the time of their discovery, work was 

 suspended. It will not be resumed for several months, when 

 it is to be hoped that enough will be obtained to supply the 



scientific world with 

 specimens. The 

 form of these crys- 

 tals is shown in fig- 

 ure 1,* the planes 

 present are : c (0001, 

 O), m (1010, I), o 

 (1011, 1), s (2051,2). 

 What Mr. Searles 

 calls " bunches of 

 hanksite " are ag- 

 gregations of flat 

 hexagonal plates 

 joined together in a 

 confused irregular 

 manner. They vary in size from an inch or less in diameter 

 to eight inches or more. One of these crystals is shown 

 in figure 2. The crystals also vary in size, the largest being- 

 three inches, and the smallest half an inch or less in diameter. 

 Some of the bunches have been accidentally subjected to the 

 action of comparatively pure water, by which partial solution 

 has taken place, not only marring the beauty of the individual 

 crystals, but leaving the clusters in a dilapidated, cavernous 

 condition. In the dark, concentrated, amber-colored water of 

 the borax lake, they remain unchanged. A rare prismatic 

 form is shown in figure 3. 



Hanksite is known to occur also in the borax fields of Death 

 Valley, Inyo County, and there are several known localities in 

 the state of Nevada. 



The following minerals have been found associated with 

 borax in San Bernardino County : 



Anhydrite, calcite, celestite, cerargyrite, colemanite, dolo- 

 mite, embolite, gay-lussite, glauberite, gold, gypsum, halite, 

 hanksite, hydrosulphuric acid, natron, soda niter, sulphur, the- 

 nardite, tincal, trona. 



It is the opinion of the writer that instead of being a rare 

 mineral, hanksite will be found in great abundance, and it will 

 be proved that it plays an important and active part in the 

 metamorphoses that produce gay-lussite, thinolite and perhaps 

 borax. 



San Francisco, October 20, 18S8. 



* These figures have been drawn by Mr. E. F. Ayres of Yale University. 



