Monchiquite, Glen Garry

From Glen Garry at the northeast edge of Lochaber. Collected from a building site, this rock exposure had probably not been seen or mapped before, and is now built upon. Handsample looks like basalt, but has different mineralogy. It contains no feldspar and little pyroxene, the mafic mineral mainly brown hornblende, kaersutite perhaps?, set in a feldspathoid matrix with ?analcime spots. Olivine phenocrysts, some altered, some completely fresh, very sharp crystal shapes.
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