. English: Diamond, a cubic carbon crystal, is the hardest known mineral. 15 September 2013, 14:48:21. Unknown 49 Rough diamond - hardest known mineral

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Size: 2236px × 2236px
Photo credit: © The Picture Art Collection / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: ., /, /., 14, 15, 21., 48, 2013, september, unknown.