Browse Items (41 total)

Chlorite, epidote, and mica are present as secondary minerals

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

Mostly quartz, oligoclase, and microcline

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

Phenocrysts of lath shaped feldspars and beta quartz

Some feldspar shows slight alteration

Plagioclase altered to epidote and flaky sericite, rock has undergone slight metamorphism

Quartz and feldspar phenocrysts, rounded diabase inclusions

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

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

Fedlspar and quartz exhibit fracturing

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

Extensively used in highway construction

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

Gabbro associated with syenite ring dike near Concord, North Carolina

Ophitic texture in thin section, some opaques

Contains biotite, orthoclase, hornblende, quartz, and titaniferous magnetite

Quartz and feldspar exhibit fracturing

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