A one-carat lab-grown diamond cost $4,200 in 2018. Today it sells for under $200.

Approximate one-carat wholesale price, natural versus lab-grown, 2018 to 2025. Dollars.

Why this is happening

Lab-grown diamonds are optically identical to mined ones but 80-90% cheaper, and a 300%-plus expansion of Indian production capacity collapsed the price.
As lab-grown flooded in, shoppers switched, and they now account for more than 45% of US engagement rings.
The glut dragged natural stones down too: the De Beers price index has fallen more than 45% from its 2021 peak, its lowest this century.

The take

Diamonds were never truly rare; their value was scarcity manufactured by marketing ("a diamond is forever") and tight supply. Technology dissolved both at once. When a luxury's scarcity is engineered, someone can always engineer it away.

Source: De Beers price index; Paul Zimnisky, Bain & Co (2025)