Amethyst is quartz — silicon dioxide, same as the clear stuff — coloured purple by traces of iron altered over geological time. For most of history that purple made it a precious stone; then an enormous Brazilian deposit was found in the 1830s and the price fell to earth, which is why you can own a good cluster for less than a haircut. Nothing about the stone changed. Only the quantity did.
What amethyst is used for
It has been the calm stone for about as long as anyone has written these things down — the name comes from the Greek amethystos, "not drunken", because the Greeks believed it kept a drinker sober. Today people reach for it for a busy mind, poor sleep and meditation. Most keep one on the nightstand or under the pillow; the tradition assigns it to the crown and third-eye chakras and to Pisces, Virgo and Aquarius.
A cluster works as a fixed point in a bedroom or reading corner. A tumbled piece is the pocket version. If you only buy one stone, this is the usual and reasonable first pick.
How to care for it
Fades in sunlight — cleanse on selenite or in moonlight. The purple is a fragile colour centre: ultraviolet light degrades it, so a sunny windowsill will slowly bleach the stone — one of the few pieces of common crystal advice that genuinely causes harm.
Related reading in the journal: Why amethyst stopped being precious.
Amethyst in the shop
Stones that keep it company
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