Malachite is especially fragile. Protect malachite from scratches and sharp blows. Also avoid large temperature changes such as leaving it by a heater vent or in a hot car. Do not clean malachite in a home ultrasonic cleaner. Washing malachite in water will remove its finish. Malachite is always coated with a protective polish. This polish will wash off. Imitation malachite has very regular black or white banding.
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