Or possibly Captain America's shield.
"yet is hard enough to dent diamonds."
Diamonds are crystalline, they can be chipped or shattered, 'pretty sure' they cannot be bent.
How much does it cost? How slick is it? Is better used as an abrasive or wear surface? How well does it conduct heat and electricity? Is it pretty?
Crystals cannot be dented? Not if you insist that they remain perfect crystals -- that includes a fixed geometry -- but real crystals don't. You'll find nice clear diagrams of how a crystal deforms at http://www.sut.ac.th/engineering/metal/pdf/MechMet/04_Plastic%20deformation%20of%20single%20crystal.pdf. With diamonds it takes big forces: but 600,000 atmospheres is a lot of force.
As for how much it costs, far too early to ask. The only samples are the ones created in a diamond anvil, probably very small. They may be so small that we don't yet know how a visible piece of the stuff would look in ordinary light. (Remember, gold in small small bits is purple!)
@yrag - Metal is crystalline and it can be bent and dented.
Fretting Freddy the Ferret pressing the Fret
You mean colloidal gold in dispersion is purple.
Anton McInerney
What a great foundation material for the Makers!
Give it to DARPA. For a few hundred billion more dollars, we'll have a new super tank and better body armor for the troops.
Dawar Saify
This substance will also have tensile strength. It could be used in strong transparent items, like bullet proof glass, and riot shields and could replace metal in some cases and in the future used in structures.
Simon Burdett
Armour piercing rounds come to mind. All the penetration without the fall out. No more "crispy critters" :-P