Pure Pearls Glossary
Yellowing
The gradual browning of old pearls as the protein binding the nacre oxidises. Usually irreversible.
Conchiolin, the protein that binds nacre platelets, darkens with age and exposure. The result is a yellow or brownish cast that dulls the pearl.
Cosmetics, perspiration and long storage in dry, sealed conditions all accelerate it.
Once the discolouration is in the nacre it cannot be cleaned out. Commercial bleaching exists but thins the nacre and weakens the pearl.
When you are buying
Prevention is the entire strategy. Wipe pearls with a soft damp cloth after wearing, and store them in a cloth pouch rather than a sealed plastic box.
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Nacre
The material a pearl is made of: microscopic aragonite platelets glued in layers by conchiolin. Thickness determines both lustre and lifespan.
Pearl Care
Pearls are soft and porous. They need to go on last, come off first, and be stored apart from everything else.
Peeling
Nacre lifting or flaking away from a pearl, exposing the bead beneath. Terminal, and caused by thin nacre or chemical damage.
Restringing
Replacing the thread a strand is built on. Routine maintenance, not repair, and overdue on most pearl necklaces.
Not sure what you are being sold?
Paste any pearl description — another shop’s listing, a message from a jeweller, an old certificate — and we will break it down term by term.