But it seems millennials — those aged between roughly 18 to 35 — aren’t as interested in buying diamonds as in previous generations.

The De Beers diamond cartel made the first concerted effort to link diamonds with engagement rings in the 1930s.

And it was wildly successful — in the 1940s just 10 percent of engagement rings contained diamonds. This had rised to 80 percent by the turn of the century.

But now that tradition is changing. Couples in the UK are spending almost a fifth less (19 percent) on engagement rings than they did five to 10 years ago, according to research from insurer Protect Your Bubble.