Answer: yttria

AnswerCrossword Clue
YTTRIAOxide of element 39
YTTRIAWhite powder used in incandescent gas
YTTRIAOxide in incandescent gas mantles
YTTRIAHeavy white powder, in chemistry.
YTTRIAHeavy, insoluble powder.
YTTRIAPowder used in color TV tubes
YTTRIAPowder used in television tubes
YTTRIARare-earth oxide
YTTRIAOxide used in television tubes
YTTRIAPowder used in lasers
YTTRIAOxide used in picture tubes
YTTRIAYellowish powder used in ceramics
yttriawhite, water-insoluble powder, Y2O3, used chiefly in incandescent gas and acetylene mantles