Is Amethyst hard enough for everyday rings?

Mostly. At a Mohs hardness of 7, Amethyst stands up to routine wear, though sharp knocks and abrasive dust can still mar it over years of daily use.

How can I tell Amethyst from purple glass?

Amethyst and purple glass can look alike to the naked eye, but they differ in measurable properties — refractive index (1.544–1.553 for Amethyst), specific gravity (2.65), and hardness (Mohs 7). A gemologist confirms the distinction with a refractometer and loupe; the Jewelry Identifier app gives a fast first read from a photo.

Does Amethyst come in colors other than purple?

Yes. Amethyst occurs in purple, violet. Color is driven by trace elements and treatment history, and it is one of the biggest factors in a stone's value.

* quartz gemstone

Amethyst: identification, value, and how to spot a fake

Purple variety of quartz. Brazilian and Uruguayan amethyst dominate the market; deep saturated 'Siberian' color is the premium grade. Heat-treating amethyst produces citrine.

Published May 30, 2026

Quick facts

Mineral family: quartz
Chemical formula: SiO2 (Fe impurity)
Mohs hardness: 7
Refractive index: 1.544–1.553
Specific gravity: 2.65
Crystal system: trigonal
Luster: vitreous
Birthstone month: February

Colors

Amethyst is found in purple, violet. The body color, its saturation, and how evenly it spreads through the stone are among the strongest drivers of value.

How to tell real from imitation

No single test settles it, but a few grounded checks quickly narrow things down for Amethyst. Hardness, brilliance, and the list of stones it is commonly confused with all give you something concrete to look for.

Scratch resistance: genuine Amethyst sits at Mohs 7, so it should resist scratching from softer materials — a stone that mars far too easily is suspect.
Brilliance & luster: Amethyst shows a vitreous luster and a refractive index of 1.544–1.553; imitations often look glassier or flatter under the same light.
Density: a real Amethyst has a specific gravity near 2.65, so it feels heavier or lighter in the hand than many look-alikes of the same size.
Commonly imitated by: purple glass, synthetic amethyst, purple sapphire. If a deal looks too good, suspect one of these substitutes first.
Fast first read: photograph the stone in the Jewelry Identifier app to estimate the gemstone and its likely value range, then confirm anything important with a gemological lab.

Common treatments

heat treatment (to convert to citrine)
irradiation

Treatments are routine for many Amethyst stones, but they materially affect value and should always be disclosed — an untreated, lab-certified stone commands a clear premium over a treated one.

What to know about Amethyst

Purple variety of quartz. Brazilian and Uruguayan amethyst dominate the market; deep saturated 'Siberian' color is the premium grade. Heat-treating amethyst produces citrine.

Sources

Wikidata Q104145

* Frequently asked

FAQ

Q. Is Amethyst hard enough for everyday rings?: A. Mostly. At a Mohs hardness of 7, Amethyst stands up to routine wear, though sharp knocks and abrasive dust can still mar it over years of daily use.
Q. How can I tell Amethyst from purple glass?: A. Amethyst and purple glass can look alike to the naked eye, but they differ in measurable properties — refractive index (1.544–1.553 for Amethyst), specific gravity (2.65), and hardness (Mohs 7). A gemologist confirms the distinction with a refractometer and loupe; the Jewelry Identifier app gives a fast first read from a photo.
Q. Does Amethyst come in colors other than purple?: A. Yes. Amethyst occurs in purple, violet. Color is driven by trace elements and treatment history, and it is one of the biggest factors in a stone's value.

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