The diamond industry offers a warning about what can happen when something built around scarcity becomes easier to manufacture. Natural one-carat diamond prices have fallen from roughly $8,007 in 2021 to about $3,898 in 2026, a decline of 51%. Lab-grown diamonds have played a role alongside excess supply and weaker demand, with De Beers reporting that wholesale prices for synthetic diamonds have fallen about 93% since 2020.