Diamond that is harder than the kind you like

[Garry H (Cut Nut)]

This diamonds stuff will never be large enough for gemstones - it only occurs naturally as a result of meteor impact and in micro sizes.
Regular diamond bonds closer than other materials, in a kind of puckered shared electron covalent 4 bond system - this stuff is similar but not 'puckered' so the bonds are even shorter and stronger.

https://www.sciencedaily.com/releases/2016/12/161212101116.htm

 

[DanJose]

It wouldn't be very fair even calling this a diamond, like graphite and diamond aren't regarded as the same materiel even though the chemical elements are identical.
This would again be a completely different materiel.

 

[Garry H (Cut Nut)]

It wouldn't be very fair even calling this a diamond, like graphite and diamond aren't regarded as the same materiel even though the chemical elements are identical.
This would again be a completely different materiel.

It does have a name - lonsdaleite, and its properties that we know are very much like diamond but probably better in most respects - but the specimens are too small to do a lot of testing with.

 

[MarionC]

Very interesting, remarkable, actually. thanks for sharing.