Browse Items (23 total)

Macroscopic: Low-grade metamorphic (zeolite facies) black siltstone with idiomorphic pyrite porphyroblasts. Microscopic: Very fine grained quartz and muscovite with large pyrite phenocrysts. Thin section picture in XPL unless noted in the picture…

Macroscopic: Slate (low grade shale metamorphism) samples with visible thin black beds. Samples were found interbedded with siltstones represented by sample NS-1. High angle between bedding and cleavage. Microscopic: Very fine grained quartz,…

Macroscopic: Argillite bearing spessartine garnet formed through reaction with the surrounding rock during metamorphism. Microscopic: Abundant medium-sized garnet phenocrysts within a very fine grained matrix. Thin section pictures in XPL unless…

Macroscopic: Biotite, muscovite schist. Parts of the outcrop are migmatic as a result of intrusion by various phases of the Port Mouton Pluton. Microscopic: Coarse grained biotite, muscovite and quartz. Thin section pictures in XPL unless otherwise…

Macroscopic: Porphyroblastic staurolite, andalusite, cordierite, garnet, biotite, chlorite, muscovite schist. Cross bedding or graded bedding may be apparent in some samples. Mineral zone: staurolite-andalusite. Microscopic: Large garnet phenocrysts…

Macroscopic: Mega-porphyroblastic andalusite, cordierite, staurolite, biotite, garnet schist. Relict bedding, cross bedding or graded bedding may be apparent in some samples. Mineral zone: staurolite-andalusite. Microscopic: Large garnet phenocrysts…

Macroscopic: Grey garnet, biotite and chlorite bearing quartzite. Likely protolith is a low-Al quartz-rich sandstone bed. Microscopic: Abundant quartz crystals accompanied by chlorite and biotite. Thin section pictures in XPL unless otherwise noted…

Macroscopic: Biotite, muscovite schist. The biotite has begun retrograding to chlorite. There is a mineral zone consisting of garnets present in the handsample. Microscopic: Abundant foliated biotite/sericite and quartz. Large amphibole phenocrysts…

Macroscopic: Porphyroblastic amphibole in epidote, chlorite, and garnet calcsilicate rock. This sample represent the metamorphism of calcarious concretions in beds of quartzite to a schist. The formation this samples comes from has considerable…

Macroscopic: Staurolite, garnet, biotite porphyroblastic, chlorite bearing, muscovite schist. Both garnets and staurolite are idiomorphic with the former highly poikiloblastic. The foliation in the schist bends around the porphyroblastic phases…

Rock Sample:
The sample has black to green phenocrysts with a greenish white matrix. It has phaneritic grains with a aphanetic matrix. Phenocrysts are coarse to fined grained ranging from 0.1~1cm in size. There is a chalk like powder on the…

Macroscopic: Biotite, muscovite schist. This sample was a part of a roof pendant, or a piece of rock the surrounded a batholith. Likely part of the silimanite zone. Microscopic: This sample under thin section displays an almost entirely mica and…

Macroscopic: Mesocratic fibrolitic double micaceous pinstripped gneiss. High reflectivity denotes a high concentration of foliated micas. Migmatized texture indicates of the rock indicates incipient melting. Microscopic: This sample contains…

Rock Sample:
The samples color has a white matrix with dark green phenocrysts. It is phaneritic. There is evidence of chemical weathering due to the presence of a dark brownish orange film on the sample--may be oxidation. There is a sandy smooth…

Macroscopic: Leucocratic biotite, muscovite, sillimanite gneiss. A banded gneiss characterized by leucocratic minerals. Microscopic: thin section shows an abundance of muscovite and quartz. Thin section pictures in XPL unless otherwise noted in the…

Macroscopic: Andalusite, biotite, garnet, muscovite, chlorite schist. Heavily weathered exterior due to divets and altered nature. High abundance of foliated mica. Microscopic: The andalusite, biotite, and garnet are porphyroblastic with andalusite…

Rock Sample:
The color of the crystals within the sample is half-white and half-black in color. The internal part of the sample feels rough, but the outside layer of the sample feels more like a fine-grained. This could be due to erosion on the…

Macroscopic: In this Chiastolite slate, the andalusite has retrograded to sericite. Microscopic: Strongly foliated sericite. Thin section pictures in XPL unless otherwise noted in the title of the picuture. Thin sections are 3mm across.

Macroscopic: An andalusite, biotite schist with large and abundant garnet porphyroblasts. Low grade of metamorphism. Microscopic: Large andalusite and cordierite phenocrysts within very fine grained matrix. Thin section pictures in XPL unless…

Macroscopic: Grey massive biotite, muscovite granite. Overall white and grey color. Only slightly weathered.  Microscopic: Abundant in alkali feldspar, plagoclase, quartz and mica. Thin section pictures in XPL unless otherwise noted in the title of…