Crown glass

crown glass

[′krau̇n ‚glas]

(materials)

A soda-lime glass, typically having 72% SiO₂, 13% CaO, and 15% Na₂O, which is hard and will take a simple polish; highly transparent for visible light.

McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

Crown glass

1. An early form of window glass, cut from blown disks.

2. The glass made by blowing a mass of molten material, which is then flattened into a disk and spun into a cular sheet.

See also: Glass

Illustrated Dictionary of Architecture Copyright © 2012, 2002, 1998 by The McGraw-Hill Companies, Inc. All rights reserved

crown glass

A handmade glass of soda-lime composition, used for windows; manufactured in the early 19th century by a now-obsolete process in which a hollow sphere of glass was blown while still very soft, then spun to form a large, nearly flat circular disk. During the spinning process, ripple lines were formed in a pattern of concentric circles, with their center at the center of the spun disk; this central area was used in a bull’s eye window. Also see glass.

McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.