February Birthstone: Which Amethyst, and What It Costs

Amethyst runs from palest lilac to a deep, rich purple. Dealers sort it into four grades, mostly by color; the names vary by seller:

1. Top grade: vivid, medium-dark to dark reddish purple or purple, no zoning visible face up. Sold as “AAA”, “extra” or “Zambian”, a name for the color even when the stone comes from Uruguay or Brazil.
2. Second grade: a little less saturated, sometimes zoned or slightly included. “AA” or “A”.
3. Third grade: light lilac, the amethyst of mass-market jewelry. “B” or “medium”.
4. Fourth grade: paler still, with a grayish cast. “Light” or “C”.

Two things pull the price down hard: a brownish tint, and zoning you can see through the top of the stone. Lay a loose amethyst table down on a white card: zoning shows best that way. And don’t chase the darkest stone: a very dark amethyst can look black in dim light.

Little, by colored stone standards: its top qualities cost not much more than its commercial ones.

What sellers asked in the listings we read between 22 October and 3 November 2026: for stones of 2 to 10 carats, about $11 to $43 a carat, the spread between three sellers’ median prices. Around one carat, too few sellers listed enough stones for a figure. Color does the sorting: light lilac is usually much less expensive than intense purple.

Size is rarely the problem: almost all faceted amethyst is eye-clean and comes in a wide range of sizes. Large stones in the deepest purple are harder to find. Against the other months: all twelve birthstones, ranked by asking price.

Yes, with some care. Amethyst rates 7 on the Mohs scale with good toughness: a good ring stone, like tourmaline or red garnet. But most dust in the air is quartz, also 7, so it scratches more easily than sapphire, at 9 (our gemstone hardness chart).

Three habits keep an amethyst looking new:

• Keep it out of long, strong light. Some amethyst fades after extended exposure.
• Keep it away from heat. An abrupt temperature change can fracture it, and a jeweler’s torch can alter its color: say it is amethyst before any repair.
• Clean it in warm, soapy water. An ultrasonic cleaner is usually safe; steam is not recommended.

On a daily ring, a setting that covers the edges helps: bezel, prong or basket. Earrings and pendants ask far less (amethyst jewelry). Want purple on your hand without a second thought? Purple sapphire and spinel are harder: see our violet gemstones, and the purple sapphires in our collection below.

Two things you cannot see by eye.

• Heating, the usual treatment. It lightens a stone that is too dark and removes brownish tints, but cannot deepen a pale one. The result is stable and usually leaves no evidence, so even a laboratory often cannot tell. Ask the seller, in writing.
• Lab-grown amethyst, on the market since the 1970s and much cheaper to grow than fine natural amethyst is to mine. Some cannot be told from natural with standard gem-testing equipment, only by a laboratory’s advanced testing, and synthetics have turned up mixed into parcels of natural stones.

Glass imitations exist too. For a stone that matters, ask for an independent laboratory report naming it natural amethyst: what a lab report proves.

Pushed further, heat turns some amethyst yellow: most citrine on the market, one of November’s birthstones, began as amethyst.