Browse Items (1651 total)

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Coarse grained

Sample found intruding into Conway Granite (WMB-7)

iron-stained

From the Concord Granite. Thin section contains plagioclase, potassium feldspar, quartz, biotite, and muscovite. Hand sample is finer grained and contains feldspars, quartz, and micas.

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Antigorite, magnetite, ankeritic carbonate, diopside, tremolite. A very marked subsequent foliation nearly completely obliterates a previous initial foliation.

Antigorite, magnetite, carbonates (ankerite), diopside, clinohumite, tremolite, chlorite. Rarely, pseudomorphs on primary pyroxenes may be recognized, though there is superimposition of various deformational phases.

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Many have large dark mineral clusters

Fine-banded, most of the bands are several inches wide and alternate light-dark

Mined and marketed under the name "Aplite"

The specimen was collected from the Oregon Dome Massif. The Oregon Dome is similar in all respects to the anorthosites described and analyzed by Buddington (1939) for the Adirondack High Peaks region (Marcy Massif). Texturally, the present specimens…

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