fossil

Abalone Shell / Mother of Pearl

Haliotis sp. (Nacreous shell layer)

Hardness: 3.5 to 4 on the Mohs scale, Color: Iridescent rainbow, pink, green, blue, and silver, Luster: Pearly (nacreous), Crystal Structure: Aragonite (orthorhombic) platelets arranged in microscopic layers, Specific Gravity: 2.65 to 2.75

Hardness: 3

Identified August 3, 2026More fossil →

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Physical properties

Formation & geological history

Formed biologically by marine gastropod mollusks (abalone) over their lifespan through the secretion of calcium carbonate (aragonite) and conchiolin to line their shells.

Uses & applications

Widely used in jewelry making, inlaid decorative arts, guitar fretboard markers, buttons, and holistic or metaphysical healing collections.

Geological facts

The iridescent property, known as nacre or mother-of-pearl, is created by the diffraction of light through microscopic layers of aragonite platelets. It is exceptionally tough due to its unique brick-and-mortar microscopic architecture.

Field identification & locations

Easily identified by its distinct concave shape, pearlescent and multicolored play of light (iridescence), and organic origin. Commonly found in coastal marine environments worldwide, particularly cold waters along the coasts of Australia, New Zealand, Japan, South Africa, and western North America.

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