Until now, the hardest diamonds have been found in asteroid and meteoroid impact craters, meaning they are rare and often very ... would not be used at scale if it were costly.

Diamonds are highly valued and expensive gemstones due to their rarity, beauty ... They have a hardness rating of 10 on the Mohs scale, which is a measure of a mineral's ability to resist ...

A rare blue diamond exceptional in both size and beauty ... Only five other auctioned blue diamonds have ever tipped the scale at more than 10 carats. The stone received the highest possible ...

That diamond on your wedding ring isn't as rare as you might think ... but on the [geological] scale of things, it's relatively common," said Ulrich Faul, a research scientist in MIT's Department ...

Fancy diamonds command a premium because of their rarity, but they also come in sizes ... They are not investment pieces on the same scale as large pink, red, green or blue diamonds, but in ...