Boundary Hill Granite

Granite is a highly variable rock type. Boundary Hill granite is variable at the local scale, but is often composed of larger crystals (>5 mm) of feldspar, quartz and mica. Many Boundary Hill rocks contain crystals of the mineral feldspar, that  measure 30-40 mm across.

And sometimes granite rocks contain remnant fragments of older rocks that were enveloped by the granite as is pushed up through the earth’s crust, melting the surrounding sedimentary rock on its way towards the surface. These structures are called xenoliths- foreign rocks now embedded in the granite.

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