The crystal market is full of dyed howlite, baked amethyst, and glass with a story attached. These guides exist so you never pay real money for a fake, and never overpay for the real thing. Honest advice, even when it costs a sale.
The five most common fakes in the market today, and the simple checks anyone can do in a shop without special equipment.
Some stones are priced on story rather than substance. Where your money goes further, without giving up anything that matters.
In traditional practice, some stones were kept apart on purpose. The reasoning behind the old rules, and the practical side of storing stones together.