Black nylon plastic with a matte finish and slight grainy feel.
About this Product
As noted by the title, this is a set of dice that are rounded like spheres. The dice are all based on a 2cm diameter sphere. Included are a 4-sided, 6-sided, 8-sided, 10-sided, 10-sided percentile (it counts by tens instead of ones), 12-sided, and 20-sided die. For more information or if you want the models for them, go to my thingiverse post at http://www.thingiverse.com/thing:676660 .