Grolleg                                     55

Custer Feldspar                      20

Pyrax                                         13

Silica                                         12

Add:

Black MS 6600                     13

Cobalt Oxide                        2

*tested on a  red earthenware body, wet to leather hard, and single fired with Mudmobile Clear Glaze to cone 04. Also successfully tested in the wood & salt kilns at Watershed at cone 10 and above.