| | | Electrowinning plate. This is almost certainly a plate that came from the electrolytic extraction of chromium from its ore, or from an electrolytic purification process.  Chromium was dissolved in a solution and electricity was used to plate it out onto an electrode.  The only difference between this and electroplating such as is done with car bumpers, etc, is the goal: In this case you don't care if it's pretty or shiny, you just want to plate out all the chromium so you can use it for something else.
 Source: eBay seller akilawolf
 Contributor: Theodore Gray
 Acquired: 5 June, 2003
 Price: $10
 Size: 1.5"
 Purity: 99.9%
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