Something that has the characteristics of glass — hard, brittle, glossy, possibly transparent — can be said to be vitreous, or glasslike. A vitreous surface works well for a kitchen counter.
The adjective vitreous, which appeared in the 1640s, is from the Latin vitrum, "glass." Since the 1660s, the gel that fills the eye between the lens and the retina has been known as the "vitreous humor," the "vitreous body," or simply "the vitreous," presumably for the gel's clear, glassine appearance. If the vitreous breaks down, becoming more liquid than gel (usually due to aging or an injury), it can be disrupted, creating vision problems.