A Caltech Library Service

The Gem Deposits of Southern California

Jahns, Richard H. (1948) The Gem Deposits of Southern California. Engineering and Science, 11 (2). pp. 6-9. ISSN 0013-7812.

[img] PDF - Published Version
See Usage Policy.


Use this Persistent URL to link to this item:


On a warm June day nearly 76 years ago, Henry Hamilton was picking his way along the brushy southeastern slope of Thomas Mountain in the Coahuila district of, southern California's Riverside County. As he crossed a small gullied area, he noticed several rough mineral fragments of attractive pink and green color. Carefully tracing the occurrence of this loose "float" material to its source higher on the hill, he encountered a ledge of light gray rock in which a few irregular cavities were lined with crystals of quartz and other minerals. Among these others were beautifully transparent pencil-like crystals of red, pink, green, and blue color. These constituted the first California discovery of gem tourmaline, a material that already had been mined in eastern parts of the United States.

Item Type:Article
Related URLs:
URLURL TypeDescription
Additional Information:© 1948 California Institute of Technology.
Other Numbering System:
Other Numbering System NameOther Numbering System ID
Caltech Division of Geological Sciences436
Issue or Number:2
Record Number:CaltechAUTHORS:20220204-174320005
Persistent URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:113280
Deposited By: Tony Diaz
Deposited On:04 Feb 2022 18:29
Last Modified:04 Feb 2022 18:29

Repository Staff Only: item control page