Browse Items (12 total)

Hand Sample: Aphanitic brown-black basalt with microcrystalline inclusions of quartz and alkali feldspar. Weathers to yellow orange. Part of a dike cross cutting granite at the Cornwall Quarry.

Hand Sample: Porphyritic diabase with coarse to very coarse grained subhedral pink-green plagioclase laths approximately 3cm in length set in a gray-black matrix. Inclusions of matrix present within plagioclase laths. Weathers to orange-brown.

Hand Sample: Holocrystalline, phaneritic, porphyritic, diorite with quratz crystals up to 3mm in diameter set in a field of smaller light gray, and dark gray crystals. Some small oxidized pyrite crystals. Very weathered on two sides to orange yellow…

Hand Sample: Holocrystalline phaneritic, porphyritic and granophyrite rich in alkali feldspar. Larger crystals or pockets of biotite and quartz also present. Rock is weathered to orange brown. Contact on one side with dark black-brown quartz-rich…

Hand Sample: Hypocrystalline, porphyritic rhyolite. 20% subhedral to anhedral biotite, quartz, and microcline (sanidine) phenocrysts. 80% grey-brown groundmass. Massive.

Samples KBR-1, KBR-2, and KBR-2A are from a vertical mass of gabbro showing progressive differentiation inward. This sample is medium grained and holocrystalline with a hypidiomorphic-granular texture. There are gray and black crystals, both ranging…

Samples KBR-1, KBR-2, and KBR-2A are from a vertical mass of gabbro showing progressive differentiation inward. This sample is medium grained and holocrystalline with a hypidiomorphic-granular texture. There are gray and black crystals, both ranging…

Samples KBR-1, KBR-2, KBR-2A are from a vertical mass of gabbro showing progressive differentiation inward.This sample is the second sample for KBR-2. This sample is medium grained and holocrystalline with a hypidiomorphic-granular texture. There are…

KBR-3 through KBR-6 are a second gabbro mass, distinguished from the first by a repetition of the differentiation cycle. The gabbro is medium grained and holocrystalline with a hypidiomorphic-granular texture. There are gray and black crystals, both…

KBR-3 through KBR-6 are a second gabbro mass, distinguished from the first by a repetition of the differentiation cycle. The gabbro is medium grained and holocrystalline with a hypidiomorphic-granular texture. There are gray and black crystals,…

KBR-3 through KBR-6 are a second gabbro mass, distinguished from the first by a repetition of the differentiation cycle. The gabbro is medium grained and holocrystalline with a hypidiomorphic-granular texture. There are gray and black crystals, both…

KBR-3 through KBR-6 are a second gabbro mass, distinguished from the first by a repetition of the differentiation cycle. Between the location this sample was collected and the location KBR-7 was collected there is a thin gabbro pegmatite that was…