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Rhyolite Drill Core

The Callahan Mining Corporation extracted copper and zinc ores from the volcanic rocks of the Castine Formation at the Harborside Mine from 1968 to 1972. This is a 48 inch-diameter core section that was drilled for a ventilation shaft.

Location: Harborside Mine, Brooksville, Hancock County

Gift of The Benenson Family

Specimen Sponsorship: $10,000

rhyolite drill core rock garden mmgm

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