358 CALIFOENIA ACADEMY OF SCIENCES. 



MINERALOGICAL CONTRIBUTIONS. 



BY A. WENDELL JACKSON. 

 (With Four Plates.) 



I desire in the present paper to add some observations to 

 those already published (see Bull. Cal. Acad. Sci.. No. 2. Jan. 

 1885) on the morphology of Colemanite, and to refer briefly to 

 California occurrences of Pyrite, Albite, Vivianite, and Azurite. 



Colemanite. 



I wish first to correct an error contained in my former paper 

 as to the locality whence the material which formed the basis for 

 the investigations recorded in the above mentioned Bulletin, was 

 obtained. It appears that for several years after the original 

 discovery of the Colemanite deposits, all knowledge of the dis- 

 covery was, for commercial reasons, kept from publication. The 

 mineral was discovered first in Death Valley, Inyo County, Cali- 

 fornia, by R. Neuschwander, in Oct., 1882, and not till April, 

 1883, were the more extensive deposits discovered by some pros- 

 pectors in Calico District, San Bernardino County, California. 



The observations published in Bulletin No. II of the Proceed- 

 ings of this Academy, were made on material which came from 

 the Calico District deposits, and not from Death Valley, as 

 therein stated.* 



Since the publication of Bulletin No. II, Mr. Coleman has 

 placed in my handa some crystallized Colemanite from Death 

 Valley, which is in part quite similar to the Colemanite from 

 Calico District, and in part entirely dissimilar in habit. 



Before speaking of these latter, however, I wish to add some- 

 thing to the descriptions hastily recorded in Appendix II of my 

 former paper. 



* The following corrections should also be made in the paper referred to : 

 On page 26, the value of p for b (— P) should be 61° 35' 12" instead of 31° 

 38' 20". On Plate II, Fig. 5 a , the projection of the edge b : a should not 

 be parallel to a : d as represented, but should be parallel to a : x. The edge 

 is correctly drawn in Fig. i a . 



