| | |   IR mirror. Gold-surfaced mirror, probably for reflecting infrared light.  Not sure why it's so thick, but maybe to dissipate heat and remain flat even while a lot of power is being reflected off it.  That's just a guess though.
 Source: eBay seller rare-chips-4-u
 Contributor: Theodore Gray
 Acquired: 17 April, 2009
 Text Updated: 17 April, 2009
 Price: $20
 Size: 2"
 Purity: 99%
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