Browse Items (47 total)

Hand Sample: Aphanitic medium gray vesicular basalt with scattered olivine crystals. Olivine crystals are scattered throughout the sample and are either growing in clusters or as single crystals. Olivine crystals range in size from 0.05cm to 0.5cm in…

Hand Sample: Dark gray, vesicular, glassy sample. Sample surface has a ropey texture with vesicles ranging from 0.01cm to 2.5cm in diameter. Sample has an iridescent luster on unweathered surfaces.

Hand Sample: Glassy, dark gray, vesicular pumice. The sample contains many small pieces of the pumice, ranging from 0.03cm to 1.5cm in diameter. Chunks of glassy pumice and volcanic ash compose sample.

Hand Sample: On cut face, aphanitic, gray basalt with light colored phaneritic crystals (~0.1 cm in size). Subparallel fractures noted across sample. Exterior of sample has been heavily weathered, resulting in the red and orange discoloration.

Hand Sample: Imperfect volcanic bomb. Aphanitic with reddish brown color. Observed mudcrack texture of surface likely formed due to weathering. Sample contains abundant vesicles (< 0.05cm in size).

Hand Sample: Apahanitic vesicular dark gray-black basalt. Larger (

Hand Sample: Aphanitic vesicular dark gray-black basalt. Sample contains numerous vesicles ranging in size from 0.01cm to 1.5 cm.