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Powderhorn Carbonatite Western Minerals Supplementary Materials
OCR PDF of supplemental information for the Powderhorn Carbonatite collection.
Prasinite
Relics of augitic clinopyroxene, albite, actinolite, chlorite, clinozoisite, and sphene. Relics of the clinopyroxene of the original dolerite are in part substituted by chlorite and actinolite in a granoblastic and metablastic matrix of albite,…
Pumice
Hand Sample: Glassy, dark gray, vesicular pumice. The sample contains many small pieces of the pumice, ranging from 0.03cm to 1.5cm in diameter. Chunks of glassy pumice and volcanic ash compose sample.
Pumice
Hand Sample: Aphanitic light gray vesicular pumice. Sample has incredibly low specific gravity due to abundant vesicles. Vesicles range in size from less than 0.1cm to 0.3cm. Some vesicles on cut face appear to be filled in with a lighter material.…
Pumpellyite Prehnite Basaltic Tuff Breccia
Rock Sample:
The color is mainly a very dark green to dark grey. Some parts of the rock exhibit greasy luster. There are some tannish white spots and some slightly larger dark brown spots. The tannish white mineral reacts with acid. There are dark…
The color is mainly a very dark green to dark grey. Some parts of the rock exhibit greasy luster. There are some tannish white spots and some slightly larger dark brown spots. The tannish white mineral reacts with acid. There are dark…
Pyroxene-quartz-plagioclase gneiss
This specimen consists of 50-60% andesine, 20-30% quartz, and minor pyroxene and hornblende. Associated with this lithology are 2-6 inch layers of pyroxene-plagioclase granulite and amphibolite. It is believed that the Royal Mountain Member gneiss…
Pyroxenite
Coarse pyroxenite, with traces of nepheline. This is the freshest pyroxenite that was found. It occurs near the nepheline syenite body in the eastern part of the complex.