Terracolor 1927 Raku Esmerelda Powder From  £14.68

This glaze is especially challenging to use and get the best from but when you master its idiosyncrasies it does produce some spectacular results.
It's very difficult to keep in suspension and quickly forms a hard pan in the bucket or container. Best applied thickly to produce the depth of colour and responds well to reduction in contact with the combustible material, quickly producing the copper lustre tones. https://www.firedclay.uk/product/vase5/