Scoria Pumice Specimen
Nice hand sample of scoria from Pisgah Crater, California.
Scoria is a vesicular (bubble-filled) type of volcanic igneous rock that forms when lava solidifies as gasses are escaping. If the composition of the rock is mafic or basaltic, as this is, there are generally fewer bubbles, and the rock type is properly called a scoria. Lava flows at the site express both pahoehoe and a’a textures, indicating a range of viscosities at eruption (sometimes the lava was more runny than others, and we can tell from the texture it takes as it cools). 2.4 oz
Pisgah Crater is a volcanic cinder cone that was active during the holocene, with estimates ranging from 2,000- 20,000/50,000 years ago for most recent activity. It is part of the Lavic Lake volcanic field, and may be the youngest of the cones, but there are no reliable data at present. The site also contains some fantastic lava tubes, and lovely black volcanic sands.
This would be a great gift for the budding geologist or scientist.
You will receive the pictured specimen.