WELCOME TO CCMGS

Learn more about the Contra Costa Mineral & Gem Society's mission, club history, and current board of directors.

JOIN OUR CLUB

Great for families and all ages, we welcome you to join our club! Learn more about the benefits of membership today and apply.

LEARN MORE

LEARN ABOUT ROCKS

Learn more about the rockin' world of geology and mineralogy through our many informative resources and fun events.

SEE RESOURCES

GET OUT AND GO

Join the CCMGS on local field trips to collection sites, and even on out-of-state trips to explore geology through first hand experience.

SEE CALENDAR

VISIT US AT OUR SHOW

Come browse and add to your collections during our annual show in November. See our calendar to get ready for what's coming!

SEE ANNUAL SHOW

CREATE KEEPSAKES

Create your own keepsakes to treasure forever from gemstones you've collected while a member! Learn more about our activities.

SEE GALLERY

75 Years of Digging Rocks Together!

In 2025, the Contra Costa Mineral & Gem Society proudly celebrates 75 years of inspiring curiosity, community, and a deep appreciation for the earth sciences. Since 1950, our club has been a vibrant hub for those passionate about geology, mineralogy, and lapidary arts in the greater East Bay Area.

Over the decades, the CCMGS has grown into an award-winning organization, earning recognition for the quality of our educational displays, craftsmanship, and community outreach. Our exhibits have consistently received top honors at regional and national shows, reflecting the knowledge, creativity, and dedication of our members.

As we mark this milestone year, we celebrate not only our rich history but also the strong, welcoming community that continues to support and shape the future of the club. Whether you're new to the world of rocks and gems or a seasoned collector, there's a place for you in our next chapter. Join our club today to start enjoying the benefits.

LEARN MORE ABOUT MEMBERSHIP

I'M READY TO JOIN CCMGS NOW

CLUB MEETINGS ARE THE SECOND MONDAY OF THE MONTH AT 7PM (SEE CALENDAR FOR ALL DETAILS) - VISITORS ARE WELCOME!

Serving Contra Costa County

of Northern California Since 1950

American Federation of Mineralogical Societies

California Federation of Mineralogical Societies

ABOUT THE CONTRA COSTA MINERAL & GEM SOCIETY

WELCOME TO THE CONTRA COSTA MINERAL & GEM SOCIETY

The Contra Costa Mineral & Gem Society is a 501(c)(3) nonprofit organization that is dedicated to supporting geology, gemology, and mineralogy hobby collecting through the promotion of recreational and educational experiences such as prospecting, mining, and the use of public and private lands to our members.

Our organization’s mission is to promote popular interest and education in the earth sciences, including geology, mineralogy, paleontology, lapidary arts, and other related subjects. We strive to foster fellowship among individuals, groups, and associations with similar interests across our local community and beyond.