Join us as we celebrate a sparkling milestone — the Contra Costa Mineral & Gem Society’s 75th Anniversary Mineral & Gem Show, happening November 8–9, 2025 at Centre Concord! For three-quarters of a century, CCMGS has inspired curiosity, connection, and appreciation for the natural wonders of our planet. This year, we’re marking the occasion with our biggest and most exciting show yet — packed with family fun, hands-on experiences, and treasures for rockhounds of all ages!

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Step inside and explore a dazzling world of minerals, gems, fossils, meteorites, crystals, beads, jewelry, and slabs from expert vendors and collectors. Discover Earth’s hidden beauty up close through live lapidary demonstrations, educational displays, and interactive exhibits that bring geology to life. Don’t miss our popular Fluorescent Tent, where rocks and minerals glow in vibrant colors under UV light — an unforgettable experience for kids and adults alike!

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New this year: meet Diablo Dan, our official mascot, and strike a pose at our fun photo booth area to commemorate the 75th anniversary celebration. Kids can enjoy rock painting, games, and family activities, while adults explore one-of-a-kind pieces, handcrafted jewelry, and gifts perfect for holiday shopping. Plus, you can test your luck with door prizes, raffles, and silent auctions throughout the weekend — with exciting finds waiting around every corner!

Whether you’re a longtime collector, a curious student, or a family looking for an engaging weekend adventure, the CCMGS Mineral & Gem Show offers something for everyone. It’s a chance to connect with local experts, learn about Earth sciences, and celebrate 75 years of community, education, and discovery!