Our images this week show a zoomed-out view of the region of the ceramic sample containing the mullite “thicket” from last week.  I am often struck by the visual similarities between SEM images, which show very small patches of a fired ceramic surface, and aerial photographs of geographic landscape.  Cracks appear like roads or fissures in the ground; protruding crystals resemble hills, mountains, or volcanoes.  Of course, in a very rough sense, ceramic “landscapes” are created by processes that do bear some relation to geology — the surface cracks and crystals shown in these SEM images form during the cooling of a silica-rich melt (vitrified, fluxed clay body with metallic impurities), as is the case with some kinds of geologic formations that form from cooling magma/lava.

K-12 STEAM Connections:  What is a typical temperature range for volcanic lava, and how does that compare to the temperatures reached in ceramic firings?  What is a typical chemical composition of lava, and how does that compare to the composition of a typical high-fire clay body?

Acknowledgments:  Part of this work was performed at the Stanford Nano Shared Facilities (SNSF) of Stanford University.