Pumice

3D Model

Pumice sample from Obsidian Dome, Mono County, CA. Erupted in 1350 CE and is “one of the best constrained prehistoric eruption dates in the world. Using tree rings, Millar and others, found that the eruptions occurred in late summer 1350 CE.” Photographed and returned to site. https://volcanoes.usgs.gov/volcanoes/long_valley/long_valley_sub_page_19.html

Geochem information: https://www.geochemsoc.org/files/7414/1269/7673/SP-3_339-354_Taylor.pdf