This page has information about the materials used for windows in space
vehicles and outer-space applications.

The cupola on the ISS uses fused quartz borosilicate window panes.
 * see https://space.stackexchange.com/questions/3830/what-materials-are-the-windows-on-the-us-segment-of-the-iss-made-out-of

Good article on fused silica strength and material properties for space use:
 * [[https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1120&context=nasapub&sei-redir=1|Transparent Armor Ceramics as Space Windows]]


= Material availability =
Silicon and Oxygen are the two most abundant materials in the moon's crust.