Sunday, June 14, 2026

Question: California’s official state gem is a rare blue stone found in gem quality only in one county on Earth. What is it, and where is it found?

Answer: Benitoite, found in a small area of San Benito County. The California Legislature named benitoite the official state gem on Oct. 1, 1985, and gem-quality stones have been found only in San Benito County. Discovered there in 1906 and identified as a new mineral species in 1907, the gem ranges from light to deep sapphire blue and is prized for its rarity.