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The essence of the colour purple, amethyst is beautiful enough for crown jewels yet affordable enough for engagement rings.

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Royal Purple

This 13.44-ct. Zambian gem displays the rich royal purple colour typical of fine amethysts.

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Antique Cut

Amethyst is available in many shapes and sizes including antique cuts.

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Eye Clean

The finest amethysts are typically eye-clean.

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Six Sided

These crystals are typical six-sided columns with tapering faces that meet in a point.

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Amethyst crystals often show purple and colourless zones.

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Distinctive Markings

Like many quartz varieties, amethyst might form radiating crystal clusters

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Buyer's Guide

Amethyst’s major attribute is its rich velvety purple or reddish purple hue. Gems that display this colour evenly—with no visible colour zoning when viewed from above—are highly prized.


Use your postcode to find a jeweller near you with GIA reports and GIA-trained staff.


Verify the information on your report matches what is archived in the GIA report database.

What to look for


The finest amethyst colour is a strong reddish purple or purple, with no brownish or bronze-coloured tints, or any noticeable colour zoning when you look at the stone from the top. If the stone becomes too dark in tone, it might look black under dim lighting.

8.65-carat Amethyst

Much of the faceted amethyst in the market is “eye clean”, meaning it lacks eye-visible inclusions. Gem professionals overlook minor inclusions when the gem is richly coloured and otherwise high quality. Often this material is used for cabochons or carvings. Visible inclusions in pale pastel-coloured gems reduce their value greatly.


Amethyst is available in a wide variety of fancy shapes, including custom cuts. Most cutting styles are calibrated in standard millimetre sizes for use in mass-market jewellery.

Fine-quality amethyst
Carat Weight

Amethyst in large sizes is not priced significantly more per carat than smaller sizes, making it a good choice for bold jewellery designs. Unlike some coloured gems, small sizes can be strongly coloured, making it easier to match sets of differently sized gems.

Amethyst Quality Factors: The Comprehensive Guide

Tips & Advice

1. Understand the difference that colour makes.

Look at different colours of amethyst side by side to understand the range of qualities available. Pale colours are more affordable than strong reddish purple tones.

2. Don’t compromise on cut.

The quality of the cut can make a big difference in beauty and brilliance. Your amethyst should sparkle in a lively way, reflecting light back evenly across the entire gem. Poorly cut gems are much less marketable and sell at a discount.

3. Work with a jeweller you trust.

If it’s important to you that you are purchasing a natural amethyst, make sure you choose a jeweller who has gemmological knowledge and is experienced with this gem.

4. When in doubt, get a lab report.

For a significant purchase an independent laboratory report can confirm that the amethyst you are buying is natural.