Browse Items (1651 total)

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Sample intruded by Osceola granite (WMB-5). Sample contains bronze colored needles of astrophyllite associated with riebeckite.

Representative of rocks throughout a line outcrop at the edge of creek

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torn right corner

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torn right corner

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Kingdom: Animalia Phylum: Mollusca Class: Gastropoda Order: Family: Genus: Species:

Show bedding, few carbonate nodules

Dark-colored slate that is slightly phyllitic.

Black slate

Kink fold in a slate from the Mt. Merino Member.

This rock is from the chlorite zone of the Barrovian metamorphic sequence (low metamorphism).

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,…

Hand Sample: Porphyritic diabase with light crystals in a dark-grey-to-black groundmass. Plagioclase 45%, Pyroxene 45%, Hornblende 5%, Olivine and Biotite 5%

Hand Sample: Holocrystalline, fine-to-medium-grained granite. Mineralogy includes potassium feldspar and quartz. One corner of rock has a mass of dark grey-brown groundmass with inclusions of plagioclase laths and anhedral grey-green crystals.…

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…

sillimanite-rich

This specimen is extremely rich in sillimanite. European geologists refer to such lithologies as "khondolites." This locality is very near some of the old graphite production sites west of Hague.
Thin section shows sillimanite, garnet, k-feldspar.