Lonsdaleite
From apm
Lonsdaleite is basically diamond with some bonds rotated such that it is hexagonal (layers ABAB) instead of cubic (layers ABCABC). Natually it occurs only as microscopic crystals. Via mechanosyntheic it will be producible in arbitrary sizes and quantities though just like any other layer pattern like ABCBABCBA or any other gemstone that is supported by the mechanosynthetic cores of the nanofactory at hand.
- Density: 3,2 g/ccm (wikipedia en) 3,3 bis 3,52 g/ccm (wikipedia de)
- Hardness: Mohs 7–8 (for impure specimens) -- (how near to Mohs 10 would be flawless atomically precise mechanosynthesized specimens ?)
