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3D3DPartially polished slab.
This huge, thick, heavy slab of chromium has a crusty greenish layer, visible on the bottom in this picture, and covering the whole back side if you look at the rotation video. This is not, as one might think, chromium oxide (which is green) but rather a coating of glass used as a lubricant during the extrusion process. The slab is heated to red heat and dipped in powdered glass to form the coating. The notion of glass as a lubricant might seem strange, but at high temperatures, why not? Juan kindly ground and polished half of one side to show how pretty chromium gets when you give it a mirror finish.
Source: Juan Jimenez
Contributor: Juan Jimenez
Acquired: 12 May, 2007
Text Updated: 14 May, 2007
Price: Donated
Size: 12"
Purity: >99%