Cullinan Diamond Mine is renowned, of course, for the mammoth Cullinan diamond – the largest ever found – which was unearthed in 1905. The mine is also the only significant source in the world of the extremely rare blue diamond. Premier Diamond Tours runs daily surface tours at Cullinan Diamond Mine, giving an illuminating trip behind the scenes.
Our guide Fran shared her encyclopaedic knowledge of the feats of engineering and the mind-boggling statistics involved in getting diamonds out of the ground and then sorting, grading, cutting and polishing them. Add to this the miles of conveyor belts, giant metal structures, thick cables and winding wheels of this massive operation and you will begin to appreciate why the finished product is so expensive.
As part of the tour, visitors can hold a replica of the uncut Cullinan diamond – all 3106 carats of it. When uncovered it was fist-sized, but there are theories that it could have been part of a larger stone, perhaps as large as a sheep’s head. The Cullinan stone was cut into nine large gems – the largest named as the Great Star of Africa – which were given to the British Royal family by the South African government. Had it indeed been bigger, it would perhaps have made a right Royal disco ball!
The stone was discovered sticking out of the side of the mine only 9 metres below the surface of a hole which is now 1.2 kilometres long, 0.5 kilometres wide and 450 metres deep – considerably larger than the Big Hole of South Africa’s other famous mine at Kimberley. Visitors can view the hole close-up. The openings of exploration shafts are clearly visible, as is the dark grey heart-shaped mark where the Cullinan stone was found.
Diamonds are formed in volcanic pipes, so the diamond field goes downwards, leading mine owners to dig ever deeper. According to geological evaluations, the mine should have a further 50-year lifespan, producing an estimated 200 million carats of diamonds.
Again unlike Kimberley which is now a historical attraction, Cullinan is still a working mine, though mining operations are now deep underground. Mine owners no longer have to worry so much about diamonds being carried off by courier pigeon, but stringent security measures are in place, including omnipresent cameras and random searches of workers.
After many years however, it seems the powers that be have decided that reward is a better incentive than punishment. If a worker identifies a stray diamond on the ground and declares it, he or she will receive the equivalent market value. But before you jack in your day job to go and toil in the mine, be aware that only a tiny handful of workers have had such a windfall find.
Initially Cullinan was mined exclusively for gems, but what had previously been dumped as gravel often included black, brown or grey diamonds. In latter years these have become crucial for industrial purposes and now make up 80% of the mine’s output. Uses for industrial diamonds include not only drilling and cutting tools, but even applications from the needle tips on record players to special paint for spaceships.
Previously even blue diamonds were classed as industrial and sold to NASA to use in lasers. Nowadays, their rarity means the astronomical heights they reached in space have been replaced by their astronomical prices on Earth where they are bought to bedeck the rich and famous.
Part of the tour includes learning more about the gem quality stones, and in particular about the 4 C’s: cut, colour, clarity and carat. Almost inevitably on any tour, one wag will suggest a 5th C: cost.
The tour culminates in the Cullinan shop where, sadly, there are no free samples, but you can see a Cullinan starcut diamond – which boasts 66 facets, rather than the standard 58 – through a magnifying glass. There is absolutely no pressure to buy, but if you have your 6th C handy (cash or credit card) this is as good a place as any to purchase your dream diamond. Alternatively, you can just dream… and drool a little.
Assuming you don’t give your credit card too much of a workout in the shop, stop for lunch and gift shopping on Cullinan town’s charming main street. Lined with jacarandas and edged with pretty tin-roofed cottages, it’s a pleasant place to round off your trip while you carefully inspect the soles of your shoes for diamond dust.
Cullinan Diamond Mine makes a great day trip from Johannesburg or Pretoria. For bookings and current pricing, please visit: www.diamondtourscullinan.co.za
If you want to learn even more about diamond mining, Cullinan is currently the only working diamond mine in the world that allows underground visits. These tours take around 4 hours and Premier Diamond Tours acts as a booking agent. The minimum age for the Surface Tour is 10yrs, and for the Underground Tour is 16 yrs. Finally, just in case you were swayed by the finders-fee policy, the minimum age for working in the mine is 18 yrs.