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Mesolite

Mesolite is a mineral (Na₂Ca₂Al₆Si₉O₃₀·8H₂O) with a Mohs hardness of 5 and a vitreous to silky luster, usually white or colorless.

A zeolite that forms delicate white needles, compositionally between natrolite and scolecite.

Mesolite specimen
Photo: Robert M. Lavinsky, CC BY-SA 3.0, via Wikimedia Commons

How to identify mesolite

  • Hair-like white needles or compact fibrous tufts in basalt cavities.
  • Very light.
  • A knife scratches it.

Often confused with

Where it's found

  • Pune, India
  • Oregon
  • Nova Scotia
  • Iceland

Uses

Collector specimens.

Rock tumbling

Not suitable for tumbling.

Did you know?

The name means 'middle stone' because its chemistry sits between natrolite and scolecite.

Mesolite FAQ

What is mesolite?

Mesolite is a mineral (Na₂Ca₂Al₆Si₉O₃₀·8H₂O) with a Mohs hardness of 5 and a vitreous to silky luster, usually white or colorless. A zeolite that forms delicate white needles, compositionally between natrolite and scolecite.

How do you identify mesolite?

Hair-like white needles or compact fibrous tufts in basalt cavities. Very light. A knife scratches it.

How hard is mesolite?

Mesolite has a Mohs hardness of 5. A steel knife scratches Mesolite, but a fingernail doesn't.

Where is mesolite found?

Notable localities include Pune, India; Oregon; Nova Scotia; and Iceland.

What is mesolite used for?

Collector specimens.

Can you tumble mesolite?

It isn't a good choice for a rock tumbler.

What is mesolite often confused with?

Mesolite is most often confused with Natrolite and Scolecite. Natrolite needles are stouter and square in cross-section. Scolecite sprays are similar; mesolite is the sodium-calcium intermediate.

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