Welcome to the Contra Costa Mineral and Gem Society!

Next meeting:
Monday, May 10, 2021

Diamonds in North America

Diamonds are found in a variety of rock types and from a wide range of geologic ages throughout the world. Recent advances in the geology of diamonds has led to the discovery of many new diamond fields. These discoveries have led to Canada becoming one of the world’s leading diamond producers. Several diamond-bearing areas are known in the United States, and more are suspected. This talk will cover the geology of diamond host rocks, diamond indicator mineralogy, areas of known diamond fields, and areas of future potential (including California).

Walt Lombardo will be our presenter for this fascinating program you won’t want to miss!  Walt is the founder of Nevada Mineral & Book Company (http://www.geologicpublications.com/our-story.html) and a geologist with more than 35 years’ experience in mineralogy and the mining industry.

Program starts at 7:00 p.m.

Meetings are currently being held on ZOOM
For meeting access information, please contact Donna-at-Albrechts.com


Our general meetings are the 2nd Monday each month at Centre Concord, 5298 Clayton Rd., Concord, CA 94521. Meeting hall opens at 6:30 p.m., meeting begins promptly at 7:30 p.m.
NOTE: In person meetings and other gatherings of the Contra Costa Mineral & Gem Society are suspended for an indeterminate time because of the coronavirus pandemic. 

CCMGS is now on Facebook!

Monthly Display Competition

Members are eligible to enter these competitions and win recognition.  As long as there are two or more items entered in the area of competition, the winner is eligible to win a cash prize!
FACETERS: Create a new project and bring it in to share. We have a special display tray to show your work off at its beautiful best!
WEARABLE ART: Bring your original work, necklaces, earrings, rings, cuffs, etc. and hang them on our special display board for everyone to see, enjoy, and vote for!
CABBERS: We have three categories for you to compete in:
NOVICE: Any member who has not won the “Pro” designation in previous years.
PRO: Any member who has won the “Pro” designation in previous years.
SHAPE OF THE MONTH: Pros and Novices compete side-by-side to create the most eye-catching cabochon in the shape of the month.

The shapes are:
January: Irregular
February: Heart
March: Round
April: Oval
May: Pear (teardrop)
June: Rectangles & squares
July: Free-form
August: Triangle
September: Auction night – no competition
October: Marquis
November: Oval
December: Holiday party – no competition