Scoria

HA-26

Hand Sample: Microcrystalline vesicular, dark-gray to black scoria. Vesicle size varies throughout the sample, ranging from larger circular vesicles with a diameter of approx. 1.5 cm on one surface and small vesicles (less than 0.1cm in diameter) on the opposite face. Sample has low specific gravity due to abundance of vesicles.

Thin Section : Groundmass composed of glass and microcrystaline grains of plagioclase. Large elongated vesicles are observed throughout the thin section.

Sample collected in January, 1969.

Volcanic Phenomena Suite - The Hawaiian Islands of Hawaii and Oahu

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