| | |   Argon-filled double-pane window. Inexpensive insulated double-page windows are often filled with argon gas because it's cheap and helps a bit to increase the insulating properties of the window.  It leaks out after a few years.
 Source: Hardware Store
 Contributor: Theodore Gray
 Acquired: 28 February, 2009
 Text Updated: 1 March, 2009
 Price: $30
 Size: 12"
 Purity: 80%
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