Amethyst Crystal Properties: A Delightful Work In Purple Hues

Amethyst is the purple that made quartz famous. It shows up in cathedral geodes taller than a person, in tumbled pocket stones, and in Roman rings, and for most of history it was valued alongside ruby and emerald. That changed in the nineteenth century when enormous deposits were found in Brazil and the price collapsed. What did not change is the material itself. Here is what amethyst actually is.

An example of a handcrafted amethyst bracelet with eclectic, matchy-matchy elements. Image links to Mercari listing for a dual-piece set.

Basic stone properties

Amethyst is a purple variety of quartz — silicon dioxide, the same compound as clear quartz, rose quartz, and citrine. It sits at 7 on the Mohs hardness scale and crystallises in the trigonal system, which is why well-formed amethyst points end in that characteristic six-sided pyramid.

Colour zoning is normal

Amethyst rarely colours evenly. Cut a crystal open and you will typically find purple concentrated near the tip and along the outer growth zones, fading to grey or near-colourless at the base. This is standard, not a defect, and it is why cutters orient stones carefully to put the strongest colour where the eye lands.

Chevron amethyst — purple banded with white quartz in V-shaped stripes — is that same zoning taken to an extreme, and it is a distinct look worth seeking out rather than avoiding.

Judging quality

Colour dominates value. The premium is on deep, evenly saturated purple with red or blue flashes visible as the stone moves. Pale, greyish, or brownish purple sits at the bottom.

Clarity matters less here than with many gems, since good amethyst is commonly eye-clean and included material is easy to avoid. Size is not a strong price driver either — large clean amethyst is common enough that scale does not multiply value the way it would with sapphire.

Caring for it

Warm soapy water and a soft brush handle routine cleaning. Avoid ultrasonic and steam cleaners if a piece has visible fractures.

The rules that actually matter: keep it out of prolonged direct sunlight, and keep it away from sustained heat — a hot car dashboard or a jeweller's torch will shift the colour toward yellow, permanently. Store it separately from topaz, sapphire, and diamond, which are harder and will scratch the surface.