A Diamond Found in a Field Was Used as a Doorstop for Years Before Anyone Noticed

In 1866, a 15-year-old boy named Erasmus Jacobs picked up an interesting transparent stone from a field near his family's farm in the Northern Cape of South Africa. He took it home, where his family used it as a child's plaything and occasional doorstop.

One day, a neighbor noticed the stone and suspected it might be valuable. The family had it appraised. The "doorstop" was a 21.25-carat yellow diamond, eventually named the "Eureka Diamond" — the first major diamond find in South Africa.

What Happened Next

The Eureka triggered the South African diamond rush of the 1860s, leading to the discovery of:

• The Star of South Africa (1869): 83.5 carats, found by a young shepherd
• The Cullinan Diamond (1905): 3,106 carats — the largest gem-quality rough diamond ever found
• The eventual founding of De Beers, which dominated the global diamond industry for 100+ years

Other Lucky Finds

• Lesedi La Rona (2015): 1,109 carats, found in Botswana — second largest gem-quality diamond ever found. Sold for $53 million.
• The Cullinan I: Cut from the Cullinan, it is the largest cut diamond in the world (530 carats) and is mounted in the British Crown Jewels.
• An anonymous Iowa farmer: In 2010, found a 9.07-carat brown diamond in his field while tilling. Estimated value: $25,000.
• Crater of Diamonds State Park, Arkansas: The only public diamond field in the world; visitors find dozens of diamonds each year

The Probability

Diamonds form deep in the Earth's mantle and are pushed to the surface by ancient volcanic eruptions. Most surface diamonds are tiny. Finding one over a single carat in the open is extraordinarily rare. Finding one large enough to be a doorstop is, statistically, the kind of event that happens to one human in a generation.

Erasmus Jacobs, who started it all, spent his finder's fee on his family farm. The Eureka Diamond is now displayed at the Kimberley Mine Museum in South Africa.