Ask Rocky

Curious about a rock or mineral you found in California? Have a question about our state's minerals? Submit your question through this portal, and Rocky's geologist friends will do their best to help you!

A friendly-looking rock.

We receive many rock identification requests and other questions about minerals, so we created this portal to improve the question-answer process.

How long will it take to get an answer? That depends on the nature of your question. We'll try to get back to you within seven days.


  • We cannot estimate the value of rock specimens nor provide appraisal services.
  • California rock identification requests and mineral questions must be submitted through this portal so they can be properly routed and fulfilled. Questions sent through other channels will be redirected here. Thank you for your understanding.

Tips for rock identification requests

Information about where your rock came from is very important when identifying a specimen. Please provide as much detail as possible. Rocky's questionnaire will prompt you for the needed information.

Photo tips

The questionnaire can accept up to five photos. The maximum upload size is 10 megabytes per file.

  • Artificial light can make your rock specimen look discolored, so use natural daylight as much as possible. Avoid direct sunlight—it causes glare and harsh contrast. A good natural light source is filtered or indirect daylight coming through a window.
  • Choose a neutral-colored background, such as gray or tan. A “gray card” for photography is best, but plain cardboard will also work.
  • Also make sure the background doesn’t have a strong pattern that distracts from your specimen.
  • Include a scale reference in the photo. A ruler is best, but a common object of known size, like a pen or a coin, also works.
  • Ensure the whole specimen is visible in the photo.
  • Also ensure the focus is razor-sharp so we can clearly see your rock’s texture.

Web page by:
California Geological Survey - Mineral Resources Program

Ask Rocky

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