How to play

A curator never guesses a mineral by looking. They run tests, and each test crosses some minerals off the list — until one is left.

The bench

  1. An unknown specimen lands on the bench. Under it, a count shows how many minerals still fit.
  2. Tap a test to run it. The result appears on the button, and the candidate count drops.
  3. When your results point to one mineral, tap its name to identify it — and read its story.

The nine tests

  • Hardness — what scratches it? (fingernail ~2.5, copper coin ~3.5, glass/steel ~5.5, or it scratches steel)
  • Streak — the colour of its powder on a white tile (often different from the mineral's colour!)
  • Luster — how light plays on it: metallic, glassy (vitreous), pearly…
  • Break — flat planes (cleavage) or an uneven surface (fracture)?
  • Heft — heavy or light for its size (specific gravity)
  • Magnet — does a magnet pull on it?
  • Acid — does a drop of weak acid fizz? (carbonates do)
  • UV — does it glow under ultraviolet light?
  • Crystal — the shape the crystal grows in (cubic, hexagonal…)

What it's good for (and what we don't claim)

MohsForge builds the diagnostic-key habit — using properties as evidence to reach an answer (a real science-and-engineering practice). It is not a brain-training program and we make no claim it raises IQ or test scores. It's the same reasoning a gem-and-mineral hall teaches, on your device.

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