The mineral journal

Few stones are faked as often as moldavite, and much of what's sold online is just green glass. Here's how to tell a genuine piece of impact glass from a melted bottle.

The letters A, AA, and AAA look official, but for crystals there's no standard behind them. Here's what grading really means, and how to judge a stone yourself.

Most crystals, polished pieces included, are fine for normal water contact. Here's the honest, geology-based truth about what actually needs to stay dry.

The bright orange "citrine" you see almost everywhere usually isn't citrine at all; it's heat-treated amethyst. Here's how to tell the real thing, the white-base giveaway, and why it matters.