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This granite block from the Deer Isle Pluton is an intrusive igneous rock consisting mainly of feldspar and quartz. Note that the grain size and color of this granite differs from the adjacent Hallowell granite slabs. In general, grain size varies with magma cooling rate; the slower the cooling, the larger the grains.

Location: Church Quarry, Stonington, Hancock County

Specimen Sponsorship: $10,000