Mollusc (non-nacreous pearl-like concretions) · Calcareous Concretions

Calcareous Concretions

Conch, melo, Tridacna and quahog concretions are wild, non-culturable 'pearls' whose porcelain lustre and flame structure set them apart from true nacre - with conch pink the most coveted and light-fading.

Colour
orange

Transparency
Translucent edges to opaque

RI
1.530–1.685

SG
2.81–2.87

Mohs
2.5–4.0

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Calcareous Concretions

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