Pearl
Pearl is biogenic carbonate (nacre), CaCO₃ (aragonite) + conchiolin. In the hand, it rates 2.5 to 4.5 on the Mohs scale, and it runs white and cream. Softly glowing nacre with subtle surface texture, rub two pearls together and they grip with a fine grittiness. Cultured: China (freshwater), Japan (akoya), Tahiti, Australia (south sea); natural pearls are vanishingly rare.
The geology.
Pearl carries the formula CaCO₃ (aragonite) + conchiolin. It belongs to the, (layered biogenic) system. Catalogues list it as biogenic carbonate (nacre).
It sits at 2.5 to 4.5 on the Mohs scale. The surface reads pearly (nacreous). Light behaviour is opaque with deep luster. Specific gravity runs 2.60 to 2.85. The streak is white. It breaks with uneven.
Softly glowing nacre with subtle surface texture, rub two pearls together and they grip with a fine grittiness.
It reaches buyers as round beads, baroque shapes, keshi or strands.
The origins.
Cultured: China (freshwater), Japan (akoya), Tahiti, Australia (south sea); natural pearls are vanishingly rare.
On value, the database notes: freshwater affordable; fine akoya, Tahitian, and south sea grades climb steeply.
Traditional associations.
In energy work traditions, associated with purity and accumulated wisdom.
We keep this section because people ask. It sits below the geology on purpose, and none of it describes something the stone does.
Spotting the real thing.
Softly glowing nacre with subtle surface texture, rub two pearls together and they grip with a fine grittiness.
Nearly all pearls today are cultured (genuine); the fakes to dodge are coated glass and plastic, the tooth test rules quickly.
| Looks like | How to tell them apart |
|---|---|
| Glass/plastic 'pearls' | Fakes are perfectly smooth, they slide glassily against teeth; real nacre feels finely gritty |
| Shell-coated beads | Coating chips at drill holes revealing white shell core |
| Mother-of-pearl beads | Cut shell shows flat banding rather than concentric nacre |
At-home tests.
Before anyone talks you into a lab report, these are the checks worth doing yourself on pearl.
| Test | What you should see |
|---|---|
| Tooth test | gentle grittiness = nacre |
| By eye | Check drill holes for coating flakes |
| By touch | Cool to the touch, warms slowly |
| By eye | Imperfections are a good sign, real pearls are rarely flawless |
Stop short of anything that leaves a mark. A gemologist can answer the rest without damaging the stone.
Care & handling.
At 2.5 to 4.5 on the Mohs scale this is a soft material. Keep it as a display piece, store it apart from harder stones, and skip daily-wear settings.
It breaks with uneven, which is worth knowing before you set it or drop it.
Skip the ultrasonic. Lukewarm water, mild soap and a soft cloth handle routine cleaning without risk.
A deeper look.
Extended detail on composition, sourcing, authentication and market value.
The physical record
The formula on record is CaCO₃ (aragonite) + conchiolin. Crystal system:, (layered biogenic). Specific gravity: 2.60 to 2.85. Streak: White. Cleavage and fracture: Uneven.
How it reaches the market
Cultured: China (freshwater), Japan (akoya), Tahiti, Australia (south sea); natural pearls are vanishingly rare.
What it gets confused with
Glass/plastic 'pearls': Fakes are perfectly smooth, they slide glassily against teeth; real nacre feels finely gritty. Shell-coated beads: Coating chips at drill holes revealing white shell core. Mother-of-pearl beads: Cut shell shows flat banding rather than concentric nacre.
What it is worth
Freshwater affordable; fine akoya, Tahitian, and south sea grades climb steeply.
Where buyers get caught
Nearly all pearls today are cultured (genuine); the fakes to dodge are coated glass and plastic, the tooth test rules quickly.
One more thing
A pearl is thousands of micro-thin aragonite layers, the iridescence is light interference, not pigment.
An education-first guide.
We do not carry pearl. This page exists because the question comes up and the honest answer is worth writing down, whether or not there is anything here to sell you.
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