Could underglazes having a velvet surface at cone 6 also fire that way at low temperatures? Yes, here is how.
AMACO V-382 RED underglaze
Lavender V-320 Bailey Ceramic Supply
V-382 Red Underglaze : (V) Velvet Underglaze
AMACO V-386 ELECTRIC BLUE underglaze
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The Holy Grail—A ^10 Clear Gloss Glaze Compatible With Amaco
problems with underglaze sticking when glaze firing? (details in
AMACO — Posts — The Studio Manager
Amaco Lead-Free Low-Fire Dipping Glaze
Underglaze
problems with underglaze sticking when glaze firing? (details in
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Could AMACO velvet underglazes fire velvet at low temperature? Yes!
AMACO Velvet Underglaze Cone 6 Test Tiles — The Studio Manager
Medium Blue Velvet Underglaze is a brilliant primary blue that is vivid at cone 05, darker at cone 5, maintaining its blue color. A clear glaze over Medium Blue will significantly darken the color at any temperature.
Amaco Velvet Underglaze 2 oz. Medium Blue