Ingredients

Ingredient Amount
Bone Ash 2.91
Pearl Ash (Potassium Carbonate) 10.68
Whiting 25.24
Custer Feldspar 6.80
Grolleg Kaolin 35.92
Silica 18.45
Add Amount
Red Iron Oxide (Spanish) 9.71

Instructions

Iron reds are mainly iron saturated, which means they contain between 5 and 10% iron oxide in the glaze recipe (most recipes use 7% or more). Iron reds with bone ash (calcium phosphate) as a source of phosphorous (phosphorous in general causes opalescence and brighter colors) typically contain on the order of 10%.

Published in "Four Ways to Red" by Dave Finkelnburg, in the Apr 2011 issue of Ceramics Monthly.