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Rock & Mineral Identification Chart and Flowchart

Classify an unknown specimen with observable evidence rather than colour alone. The account-free interactive flowchart first separates rocks, dominant minerals, and uncertain or possibly manufactured material, then routes rock users by texture and mineral users by an independently verified physical clue. Choices stay in the browser tab and are not retained by GeoMiner. For rocks, use texture and grain relationships to separate intrusive and extrusive igneous rocks, clastic and chemical sedimentary rocks, and foliated or non-foliated metamorphic rocks. For minerals, begin with metallic or non-metallic lustre, then compare hardness, streak, cleavage or fracture, magnetism, relative heft, crystal habit, and geologic context. The printable chart includes common examples, a cautious field-hardness ladder, safety limits, and direct links to GeoMiner Quick ID and reference procedures. Both tools create a field-screening route rather than a laboratory determination, assay, appraisal, engineering decision, or safety clearance.

Verification resources

Cross-check terminology, classification, methods, and safety with these authoritative external resources.

  • Mineral ID Key — Mineralogical Society of America. Physical-property identification methods, repeat-testing guidance, and limitations.
  • Collecting Rocks — U.S. Geological Survey. Field context, specimen observation, and responsible rock-collecting guidance.
  • How Rocks Are Classified — U.S. National Park Service. Rock-group classification using composition, texture, and geologic processes.
  • Silica, quartz — Canadian Centre for Occupational Health and Safety. Occupational-health guidance for crystalline silica hazards and dust controls.

Read GeoMiner's editorial methodology.

Common questions

How do I use a rock and mineral identification chart?
First decide whether the specimen is a rock, one dominant mineral, or manufactured material. For rocks, follow texture and grain relationships. For minerals, begin with lustre and combine hardness, streak, cleavage, magnetism, heft, habit, and context.
Can I identify a rock from colour alone?
No. Weathering, impurities, lighting, and different materials sharing the same colour make colour unreliable by itself. Use texture for rocks and several physical properties for minerals.
Is this printable chart a laboratory identification?
No. It is a field-screening and learning aid that helps create a defensible shortlist. Important health, value, engineering, environmental, or regulatory decisions require qualified examination or laboratory evidence.
Which mineral tests are safest to start with?
Begin with non-destructive observations: context, fresh existing surfaces, lustre, crystal habit, cleavage, magnetism, and relative heft. Avoid taste, dust, flame, grinding, and casual chemical tests.

JavaScript is loading the interactive GeoMiner experience. The identification tools provide educational candidates, not laboratory confirmation.