Tholeiitic Basalt

Title

Tholeiitic Basalt

Identifier

HA-12

Description

Hand Sample: Aphanitic vesicular dark gray-black basalt with larger light crystals throughout the sample. The vesicles throughout the sample are elongate in shape, and range in size from 0.5 cm to 2.5 cm. Sample surface displays rough AA texture.
Thin Section: Groundmass of plagioclase, interstitial glass, and microcrystals of clinopyroxenes. In the picture, there is a large plagioclase phenocryst.

Date

Sample collected January, 1969

Contributor

Western Minerals

Spatial Coverage

Northern face of Mauna Loa - Island of Hawaii
Collected from Saddle Road

Temporal Coverage

1943

Number of Thin Sections

1

Geolocation