Pearl Care and Cleaning Guide

Mohs Scale
Pearl’s Mohs hardness is 2.5, so care should be taken not to scratch it.
Gem and mineral hardness is measured on the Mohs scale. The numbers are based on the relative ease or difficulty with which one mineral can be scratched by another. But the Mohs scale is deceptive. The steps between the minerals are not evenly spaced. For example, diamond is only one number away, but it’s much harder than gems in the corundum family.

Pearl is ranked 2.5 on the Mohs hardness scale, which means it’s very soft and easily scratched or abraded. But with reasonable care, pearl jewellery can be a lasting treasure.

Pearl’s toughness is usually good, but ageing, dehydration and sometimes excessive bleaching during initial processing can make some pearls more fragile.

High heat can burn cultured pearls or cause discolouration, splitting or cracking.

Pearl is generally stable to light, but heat from intense light can cause dehydration and cracked nacre.

Pearl can be damaged by many chemicals and all acids. The list includes hair spray, perfume, cosmetics and even perspiration.

Pearls might be dyed, impregnated or coated. These treatments might alter over time. Bleaching and irradiation can be stable during normal wear.

Dyed freshwater cultured pearls
The colours of these freshwater cultured pearls are the result of dyeing. Dyed pearl colours can alter over time.

Pearls should never be cleaned in an ultrasonic or steam cleaner. It’s safe to use warm, soapy water for occasional, thorough cleaning. If the pearls are strung, be sure the string is completely dry before wearing.

For routine care, it’s best to wipe cultured pearls with a very soft, clean cloth after each wearing.

Cultured pearls
With proper care cultured pearls can provide their owner with a lifetime of enjoyment.
- Courtesy Albert Asher Pearl Co., NY