Where can I identify a rock or mineral?

r/whatsthisrock is built for identification. r/geology accepts ID requests only as comments in its monthly pinned thread.

Where to ask

r/whatsthisrock

Best for: Identifying rocks and minerals you found.

Why it fits: Its public description: “Dedicated to identifying mysterious rocks and minerals.”

Rules to know before posting:

• Post several clear, detailed photographs, including close-ups.
• Top-level replies must attempt an ID or ask for more information.

Read r/whatsthisrock’s current rules on Reddit

r/geology

Best for: Science discussion; IDs only in the monthly thread.

Why it fits: Its public description: “The scientific study of the origin, history, and structure of the Earth.”

Rules to know before posting:

• ID posts must be top-level comments in the monthly pinned thread.
• No homework, exam or lab questions.

Read r/geology’s current rules on Reddit

Before you post

• Photograph it wet and dry, in daylight, with a coin for scale.
• Say where you found it, and whether it is magnetic or scratches glass.
• Mention any “meteorite” suspicion plainly — those claims are checked closely.

Rule summaries are paraphrased from each community’s published rules (public archive copy retrieved 7 November 2026; original snapshot date unavailable). Current rules may differ — check the community’s rules before posting. A good fit does not guarantee a reply.