Tuff Buff is another clay type that has particles of iron large enough to create these speckles during a reduction firing. The glaze here is butterscotch, one of my favorite for the gradient of shades produced depending on the glaze thickness. The glaze is more cream where it is thicker, and more of a rust brown where it is thinner.
Firing: Reduction high fire
Clay: Tuff Buff
Made with glazes at Echo Ceramics
Sold for $30