(Formerly Cassius Basaltic)
Fired Shrinkage is 14.5% and Water Absorption is .5%
when fired to cone 5. Very black, ebony like finish. Contains no talc. Needs lots of oxygen during bisque firing. Please refer to this link for our bisque firing schedule that was created with Obsidian in mind.
ā WARNING - This product can expose you to crystalline silica (quartz) which is known to the State of California to cause cancer. For more information, go to www.P65Warnings.ca.gov