Pure Pearls Glossary
Karat vs Carat
Karat measures gold purity out of 24. Carat measures gemstone weight. They sound identical and mean entirely different things.
24 karat is pure gold. 22K is 91.6% gold, the Indian standard for jewellery. 18K is 75%, harder and more suitable for stone settings.
One carat of gemstone weight equals 0.2 grams. It describes mass, not size or quality, so two one-carat stones can look very different.
Pearls are the exception in both systems. They are traditionally measured by millimetre diameter, and sometimes by momme, an old Japanese unit of weight.
When you are buying
When a listing says carat about metal, it means karat and the seller is being careless with terminology. Ask which number they actually mean before comparing prices.
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Hallmark
An official stamp certifying precious metal purity. In India, BIS hallmarking is mandatory for gold jewellery.
Gold Plating
A thin layer of gold deposited over a base metal. Gives the colour of gold at a fraction of the cost, and wears off over time.
Cubic Zirconia
A hard, brilliant lab-made stone used as a diamond substitute. Called American diamond throughout the Indian trade.
Pearl Size
The diameter of a pearl in millimetres, measured across its widest point. Price rises steeply, not evenly, with size.
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.