- 1). Buy amethysts from a reputable and trusted jewelry store whose staff has experience with gemstones in general and amethysts in particular.
- 2). Ask if the stone has been treated in any way. Some common treatments to enhance gems include irradiation, heat treatment, dyeing and coating. Not all of these treatments will devalue the stone, but always ask so you know what you're getting.
- 3). Look at the color of the stone. Deep purple amethysts are rarer and more valuable than light-colored ones. Also, look for rose-colored accents within the overall deep purple color as you turn the stone. Amethysts with this feature are especially valuable.
- 4). Make sure the gem has perfect clarity with no visible flaws.
- 5). Check the cut of the stone. Make sure the surface of the amethyst reflects light evenly and that there are no scratches. Turn the stone around in your hand and examine it from all sides.
- 6). Compare several amethysts side by side. Evaluate color and cut, and choose your favorite one.
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