Because amethyst is only a moderately hard gem about a seven on the Mohs scale
you can clean it with a soft bristled brush, but be careful to store it away from other jewelry, or in its own cloth or plastic bag. Do not expose amethyst to chemicals, acids, oils, or cosmetics, as they could dull the luster or even alter the color. This includes pool water and salt water. And unless you want your amethyst changing colors on you, make sure you store it out of the sunlight and avoid extreme temperatures. Never steam clean amethyst jewelry.