[Etheryte]

This is downright silly and wrong. Diamonds are not expensive because they're a cut above other gems, they're literally only expensive because of a monopoly that upholds artificial scarcity. Michelin star restaurants are expensive because they do culinary arts on the highest level. Diamonds are expensive only because one family owns all the mines.

[BoingBoomTschak]

You forget the other side of the equation: very rich people or "suckers" are ready to pay that much for it.

[dialup_sounds]

De Beers hasn't had a monopoly in decades and is no longer majority owned by one family.

[postalrat]

This isn't an ordinary diamond.

[ErigmolCt]

A product of market control