Diamond is one of the hardest materials known to man, but experts think it can be squashed into something even harder. The precious stone is a naturally occurring substance made of carbon crystals. It ...

In diamond, each carbon atom is bonded to four other carbon atoms in a tetrahedral arrangement ... material to be diamond with a hexagonal structure, rather than the classic cubic diamonds ...

The crystal structure is also known as diamond cubic and may be thought of as two interpenetrating ... The hexagonal wurtzite structure has the sulphur ions in an hcp array and one-half of the ...