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Southern Beach

Iwo Jima, Ogasawara city, Tokyo, Japan

IMA approved name

Albite var. andesine


Field of view: 7 mm. Dispatched crystals of andesine. The tabular gray crystals are andesine. The black crusts on andesine are volcanic glass. This specimen has been referred to as crystal lapilli but it seems to be phenocrysts dispatched by weathering from a glassy matrix of the andesitic intrusive rock (Motoyama dike). Andesine-Glass groups rounded well at the seashore have been called "Uzura-ishi", egg of Japanese quail, by local people as its texture is similar to the egg.

Recovered from pebbles on a seashore of a andesitic volcano in an oceanic arc.

Andesine from this location was described in 1901.

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