Amethyst Stone Guide

Amethyst is purple quartz (silicon dioxide). Most amethyst forms in geodes and large pockets, particularly in Brazil and Uruguay. Heat treatment can change amethyst to citrine or to pale greenish prasiolite, which is why the three are often discussed together.

Pale lavender to deep saturated purple. The most prized colour is a strong, slightly red-purple sometimes called "Siberian" after the historical Russian source. "Rose de France" is a trade term for pale lavender amethyst. Some amethyst shows visible colour zoning, with darker and lighter bands inside the stone.

Amethyst is 7 on the Mohs scale with good toughness. Suitable for everyday rings, earrings and pendants. The main risk is colour fading from prolonged exposure to strong sunlight or intense heat, so avoid leaving amethyst jewellery on a sunlit windowsill for long periods.

Colour is the main value driver. A deep, saturated purple with red flashes is worth far more than a pale lavender. Eye-clean clarity is the norm at all sizes. Cut matters because amethyst is cut for colour and brilliance, and a poor cut can leave windowing in the centre of the stone.

Most amethyst is untreated. Some lighter material is heat treated to produce citrine (yellow to orange) or prasiolite (pale green). Brazil is the largest producer. Uruguay produces deeply saturated stones at smaller sizes. Other sources include Zambia, Russia, South Korea and Arizona.

Cocktail rings, pendants, drop earrings and statement necklaces. Amethyst is large and dramatic at sensible prices, so big bold pieces are easy to make. Amethyst eternity bands and dress rings work well in white or yellow gold. Amethyst pairs nicely with diamond accents in vintage-inspired designs.

Clean with warm soapy water and a soft cloth. Ultrasonic cleaners are generally safe. Avoid prolonged exposure to strong sunlight or intense heat, which can fade colour. Keep away from harsh chemicals.

Amethyst is one of the most affordable coloured gemstones, even in large sizes. Premium "Siberian" colour stones are more expensive but still very attainable compared to fine sapphire or ruby. Big eye-clean amethyst over 10 carats is realistic on a modest budget.