Answer: smalts

AnswerCrossword Clue
SMALTSBlue pigments.
SMALTSDeep-blue pigments.
SMALTSPowder blues.
SMALTSDeep blue colors.
SMALTSBlue glasses.
smaltscoloring agent made of blue glass produced by fusing silica, potassium carbonate, and cobalt oxide, used in powdered form to add color to vitreous materials
smaltsSMALT, a blue pigment