Coloured Gemstone Feature: Journey of a Congolese tourmaline from mine to cutter to listing on Gembridge


By David Brough

Gem dealer Ejder Kaya, new to the business, set out to buy tourmalines from the Democratic Republic of Congo (DRC) and to curate the stones during their journey from mine to cutter to their listing on digital trading platform Gembridge (

Here is the story of one piece of rough tourmaline and its route to market:

Ejder was in Kigali, capital of Rwanda, in February 2020, looking to finish a business deal unrelated to gems but it did not come off, so he decided not to waste the trip and find something else to work on. A local friend, who was in the gem business, suggested tourmalines – there were known to be quality stones from the Rubaya mines just across the border with DRC.

Ejder Kaya with a colleague in Goma, DRC

Ejder Kaya with a colleague in Goma, DRC

Ejder consulted by phone with a Swedish gem cutter for advice and then decided to travel to DRC with his Rwandan dealer friend to source rough tourmalines. He ended up buying 13 pieces.


Rough tourmaline later cut into stones listed on Gembridge

Rough tourmaline later cut into stones listed on Gembridge

The journey overland to the border town of Gisenyi was routine but then he had to pay a hefty fee for a visa to cross into Goma in DRC.

In Goma he met with local dealers connected to Rubaya in two days of meetings at a modest hotel brokered by his Rwandan dealer friend. He  consulted with the Swedish gem cutter on Whatsapp for advice about the stones he was inspecting, sending images, and then bought the pieces of rough for cash.

The same day he crossed back to Gisenyi. He organised his export papers for the rough tourmalines and flew with the stones to Brussels.

The cutter

Two months later, after finding online a renowned gem cutter in Idar-Oberstein, Germany’s gem-cutting centre, Ejder travelled to meet him.

Bernd Cullmann was over 80 years old and well-established in the trade.

A modest man, Bernd had won a gold medal as a sprinter in the Rome 1960 Summer Olympics.

Ejder had got along well with him on the phone as they discussed one of the pieces of rough, which was green at one end and pink at the other.

During their meeting in Idar-Oberstein, Ejder handed over the rough and Bernd got to work.The tourmaline during the cutting process

The tourmaline during the cutting process

A few days later, Bernd had completed his task, handcrafting two fabulous tourmalines – a 43.50-carat green pear-shaped tourmaline and a 15.50-carat heart-shaped pink tourmaline.

For Ejder there had been huge risks in acquiring the rough: as someone new to the business, he could not be certain that the rough would yield exceptional stones, but it did.

The platform

Ejder discovered Gembridge as an ideal platform to sell the stones and after a discussion with Tony Brooke, Chairman of Gembridge, decided to list them.

The 43.50-carat green tourmaline is listed as Gembridge lot 280 and the 15.50-carat pink tourmaline is Gembridge lot 279.

“We were impressed by Ejder’s entrepreneurial and open approach, purchasing directly at the source and following the gems through a responsible and transparent production process,” said Helen Molesworth, Gembridge’s Head of Business Development.

“Not only does this fit in with our ethics and disclosure policy at Gembridge, but it tells a real story of the journey of these beautiful gems, and their added value along each step of the supply chain.”43.50-carat green tourmaline

43.50-carat green tourmaline (Gembridge lot 280)15.50-carat pink tourmaline

15.50-carat pink tourmaline (Gembridge lot 279)

Ejder gained a lot of satisfaction from accompanying the stone on its journey from rough to cut and polished, becoming part of a transparent mine-to-market supply chain which gave the best possible outcome to the remarkable rough.

The stones’ listings can be seen via these links:

Please register on Gembridge if you are a member of the gemstone trade and are considering a purchase, via this link: