I found this combination from Mayco's combinations list on their website and has been one of my favorite and best selling commercial glaze combinations. The phase separation is incredible with all sorts of colours produced whites, blues, reds, browns etc. Works best on a white clay body (didn't like my red bodies at all).
Clay Body
Name: Plainsman Clays Medium Temperature Clays M370
I'm looking for any combination (click to add filters).
Third Layer
Glaze: Mayco Stoneware SW128 Cordovan
Application Method: Brush
for food safety I would recommend probably leaving the inside a single glaze (either one) as I have not tested the combination for leaching. Depending on your coat thickness, you may want an additional coat of Cordovan, however to much can result in more rusty brown colours (like the lid of this jar).