Rock Identifier — What Rock Is This?
Found a rock and want to know what it is? Upload a photo for a free identification with an honest confidence score, likely look-alikes, and the simple field tests that confirm it. Built to admit when a specimen is ambiguous instead of guessing.
How to photograph a rock for identification
- • Show a freshly broken or cut surface if you can — weathered outer crust hides the real texture and color.
- • Include something for scale, and capture the grain: are the crystals visible, or is it smooth and fine-grained?
- • Use daylight and avoid wetting the rock unless you note it (water deepens color and sheen).
- • A second photo of a different face often helps with layered or banded rocks.
Rocks our identifier recognizes
Common igneous, sedimentary and metamorphic rocks — including granite, basalt, obsidian, sandstone, limestone, conglomerate, marble, gneiss, schist, slate and quartzite — plus the rock-forming minerals you'll find alongside them.
Three quick tests to confirm a rock
- Acid fizz: a drop of vinegar that fizzes signals a carbonate rock like limestone or marble.
- Hardness: can it be scratched by a steel knife (≈5.5)? Soft, scratchable rocks rule out hard quartz-rich ones.
- Texture & layers: interlocking crystals point to igneous; visible layers or grains to sedimentary; banding or sheen to metamorphic.
Frequently asked questions
What kind of rock is this?
Upload a photo and the identifier will name the most likely rock and its family — igneous, sedimentary or metamorphic. Rocks are mixtures of minerals, so texture and grain size matter as much as color; the tool weighs all of these and tells you how confident it is.
How do I tell igneous, sedimentary and metamorphic rocks apart?
Igneous rocks (granite, basalt) form from cooled magma and have interlocking crystals or a glassy/bubbly texture. Sedimentary rocks (sandstone, limestone) form in layers and often contain grains or fossils. Metamorphic rocks (gneiss, schist, marble) show banding, foliation or a sugary recrystallized texture.
Is it a rock or a mineral?
A mineral is a single chemical compound (quartz, pyrite); a rock is a naturally occurring mix of one or more minerals (granite is quartz + feldspar + mica). If you see many different grains, it's likely a rock — if it's one uniform substance or crystal, it's probably a mineral.
Is the rock identifier free?
Yes — your first 3 identifications are free. Unlimited IDs plus value, authenticity and care reports come with Pro.
Think it might be a crystal or gemstone instead? Try the crystal identifier