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scoria - hand/display specimen of maroon scoria from a satellite cone on Mauna Loa

$ 10.50

Back in stock soon.

Scoria is the silica poor equivalent of pumice. Lava with a low silica content is runny, so gas bubbles tend to coalesce to form larger bubbles in basalt. In a silica rich granitic magma, high viscosity prevents bubbles from coalescing, so there are many more, but smaller, gas bubbles in pumice, one reason it floats longer in water.

This scoria is surprisingly light and is amazingly red from the oxidation of hematite. It was collected at an elevation of 10,500 feet on the north slope of Mauna Loa, from a mass of blocks, scoria and cinder associated with a satellite cone that was quarried for road material. An interesting example from a famous volcano.

Select a specimen: You can select a specimen by telling us what is in the photo with it, a blue or black and silver pen, a black mechanical pencil or one of those plus some number of coins, or you can let us make the selection.

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Ships in a First Class package unless combined with other items.