Clean your Emerald with a soft, dry cloth. Avoid sudden temperature changes, household chemicals and ultrasonic jewelry cleaners. Emerald is often treated with oil to fill fissures and fractures that are characteristic of emerald. Hence, You should never clean an emerald in an ultrasonic cleaner because this oil could be removed or damaged, making the fissures more visible. In addition, do not clean emerald in hot soapy water since it too can remove this oil.
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