Caldera Glass Glasstops are formed into the bottom surface of 2” thick kiln formed glass. Hundreds of small, circular air bubbles float throughout the glass, as if frozen in time. The circular edges use our smooth, “Satin” texture, to create contrasting surfaces. A matching shell textured edge is also available, as well as highly polished clear edges. Nathan Allan’s custom furniture glass tops, can be produced in 1.5” thick to 4” thick glass. Suitable for any applications like glass tops, bar tops.