Browse Items (1651 total)

Some chlorite

Sillimanite has been partly psuedomorphed

More quartz than sample 12

Biotite is variable in amount, but it is always evenly distributed

Exhibits a runic texture, the kind that is found in feldspar mining operations (undesirable due to high amount of quartz)

Quartz and feldpsar grains are closely interlocked and grains appear to be shattered

Quatz appears strained, microcline is altered to muscovite and sericite, biotite is altered to chlorite

Extensively used in highway construction

Fedlspar and quartz exhibit fracturing

Quartz and feldspar exhibit fracturing

Biotite forms lineation in some hand specimens, much of the quartz and feldspar is fractured

Biotite and feldspar are aligned, giving the rock a texture like porphyroblastic gneiss, some feldpsar has been altered to sericite, and some larger feldspar crystals are fractured

Contains orthoclase, ligoclase, and quartz phenocrysts and has alterations of kaolinite, sericite, and epidote

Phenocrysts of lath shaped feldspars and beta quartz

Quartz and feldspar phenocrysts, rounded diabase inclusions

Contains inclusions of relict gabbro

Contains augite, amphibole, plagioclase, ziron, opaques, and a fine-grained alteration product (unknown)

Similiar in composition, texture, and shape to the Concord, North Carolina complex

Contains sutured grain boundaries, conversion of hornblende to magnetite, and some fine-grained alteration products

Some feldspar shows slight alteration