protoclay: a primordial glimpse Posted on April 13, 2022April 19, 2023 by bob Title: Oh, yes you can (can get blood from a stone)!: protoclay egg (fired granite),12 cm long, cracked and fissured, with the cone 6 bisque firing, red glaze at cone 02 oxidation PS. Featured imageTitle: J’ arrive, protoclay egg (granite), 16 cm, bisque fired to cone 5+, beginning cracks stained with ground iron oxide in water medium, cone 2 second firing, oxidation.