Spending insane amounts of money on a clump of carbon molecules to declare your love seems to me extremely wasteful. If your s.o. really needs a display of conspicuous consumption over spending your - now joint - funds carefully and wisely you might want to talk it over. Easy come easy go, if you have money left over to throw it out more power to you but most people are not in a position to throw away money like this.

Congratulations to the DeBeers marketing department, they've done an excellent job of making people believe this sort of stuff is needed.