Ravenscrag Slip iron crystal glaze fired at cone 10R on porcelains. The recipe is simply 90% Ravenscrag Slip and 10% iron oxide.
GR10-L - Ravenscrag Iron Crystal
Plainsman Cone 10R Ravenscrag Slip based glaze. It can be found among others at http://ravenscrag.com.
Ravenscrag web site
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