glassy

resembling glass in smoothness and shininess and slickness; "the glassy surface of the lake"; "the pavement was...glassy with water"- Willa Cather

(used of eyes) lacking liveliness; "empty eyes"; "a glassy stare"; "his eyes were glazed over with boredom"

(of ceramics) having the surface made shiny and nonporous by fusing a vitreous solution to it; "glazed pottery"; "glassy porcelain"; "hard vitreous china used for plumbing fixtures"