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The Banjarmasin Diamond: Gem With a Questionable History - Royal Coster Diamonds

The Banjarmasin Diamond: Gem With a Questionable History

About Banjarmasin

During the Golden Age, the Dutch government had various colonies. One of these colony regions was Borneo, what later would become Indonesia. In Borneo was a well-known island city: Banjarmasin. From the 15th to the 19th century, this area was a well-known center for trading high-quality gems from India. But they also traded many locally found stones here that had exceptional brilliance. During the 18th century alone, the Dutch retrieved around 50,000 carats of diamonds from this area. Banjarmasin mining installationTraditional mining installation in Martapura (close to Banjarmasin), Indonesia.

Diamonds from the Sultan

In 1835, Dutch scientists went on an expedition to Banjarmasin. Here, they met the ruler of the island, Sultan Panembahan Adam. The sultan was eager to show his guests to his beautiful region. Among other things, he arranged traditional performances by some of his most talented subjects. Instead of the nature of the entertainment, or the impressive castle, something else caught the scientists’ eye. It was the Sultan himself. He wore the most precious jewels and gemstones. Later on, they found out the Sultan owned an immense amount of diamonds and gemstones. Since the Sultan only received some sort of “allowance” from the Dutch Government, it was a mystery how he got them. The Dutch were intoxicated by the Sultan’s wealth. In 1859, they confiscated his treasures. A few years later, they shipped them all to the Netherlands.

The Banjarmasin Diamond

The Dutch government decided to make an inventory of the ill-gotten treasure. Among all the riches, they found a big rough diamond. It weighed around 70 carats. They named the diamond after the famous place: Banjarmasin. First, they offered it as a gift to King Willem III. But he refused the stone, probably because it cost a fortune to repolish it. Since it was such a special specimen, they sent the diamond to the Dutch Museum of Natural History for display. But the museum did not want the stone. It was not clear whether this was because of moral objections or something else. That’s when the Minister of Colonies tries to sell the diamond. However, again nobody wants the Banjarmasin.

Who wants to buy a diamond?

The Minister decided it must have been the size of the diamond that scared buyers away. That’s why he decided the diamond needed cutting. The firm E. and J. Vital Israels’ recut the 70-carat diamond. They made it into a square-ish shaped 36-carat diamond. However, still, buyers stayed away from the “stolen stone”. The reduced size was still not attractive for buyers. The last resort was to display the altered diamond at the national museum, the Rijksmuseum. But to make matters even worse, the museum declined as the diamond did not have any historical significance anymore. The stone went to E. and J. Vital Israels again. Maybe they were able to sell them. But no, they also couldn’t find any buyers for the diamond. In 1902, the government decided to give up. They took the Banjarmasin Diamond back and stored it.

Indonesian diamonds

Meanwhile, history repeats itself. The Rajah of Lombok loses his kingdom to the Dutch who confiscated all treasures. Among these treasures are again diamonds, gemstones, and jewels. E. and J. Vital Israels appraise the jewels. Some stones were sold, other pieces went to the Rijksmuseum for display. They had a special exhibition of looted riches from Lombok. Now there was a place for the Banjarmasin Diamond as well. Finally, people could see it. In total, it was on display for three months and seen by around 23,000 people. The purpose of the exposition was to educate the Dutch about colonial history. Mainly to recall sacrifices in the colonies for the benefit of the fatherland. The diamond had to remind visitors of the history of Dutch "military operations" and fulfill them with national pride and colonial power relations. Banjarmasin diamond on display with other items from LombokBanjarmasin diamond on display with other items from Lombok (source: Caroline Drieenhuizen).

Back to Indonesia?

When World War II ended, Indonesia as we know today was established. When the Dutch lost their colony, the diamond lost its created symbolic significance as a national trophy. Around 250 confiscated pieces were returned to Indonesia. But the misfit Banjarmasin Diamond was not among them. The Dutch government stored it away again for many years.

On display

Some people are late bloomers. Perhaps we can say the same about diamonds. In 2001, the Banjarmasin finally appears on display again. But this time in Paris at the Muséum National d’Historie Naturelle. Today it is on public display at the Rijksmuseum.

The Banjarmasin Diamond at the Rijksmuseum

For museums, it can be difficult to display a diamond with such a questionable past. And the Banjarmasin is no exception to the rule. Since the reopening of the Rijksmuseum, the diamond is on display again the "The Netherlands overseas" room with the intention of exposing violence in the colonies with its provenance.

Let’s check the Banjarmasin Diamond out

Royal Coster Diamonds and the Rijksmuseum are literally neighbors. Obviously, we had to check out this diamond. On a rainy afternoon, we went to the museum to see the Banjarmasin. After walking around for a couple of minutes, we found it. Safely stored in a glass box, there it was! It is always amazing to see a diamond of this size. However, I also understand why so many people refused this stone to begin with.

Banjarmasin diamond close up

Characteristics of the Banjarmasin

Rough, this diamond was assumedly around 70 carats. When the diamond workers turned the gem into a 36-carat polished stone, it lost almost half its size. They cut the diamond into a rectangular(ish) shape. A cutting loss of almost 50% is a lot, but not unusual for a diamond this shape and size. The full description of the Rijksmuseum is: “White, slightly square cut diamond of thirty-six carats from Banjarmasin.” Other characteristics are:
  • Size: l 2.1 cm × w 1.7 cm × h 1.4 cm
  • Weight: 7.65 gr

Why did no one want the stone?

This may have to do with the fact that it was a war booty. But it may also have other reasons. The color is beautiful. There is no doubt about that. But - I’m sorry to say - it is not a very pretty stone. You see, the Banjarmasin Diamond contains a lot of big and different imperfections. Many of these are natural damages. Considering their size, these are tricky or nearly impossible to get rid of. But I also see some man-made imperfections.

Man-made imperfections

Besides the man-made imperfections (such as a beard), I also noticed that the facets aren’t placed 100% correct. This can have multiple reasons. The cut is the only one of the 4 C’s a diamond worker can influence. When a polish is bad, it can be because the diamond polisher isn’t skilled enough. But it can also be because of inadequate equipment. In this case, I can’t tell you which of the two it is. I do think that they could have done a better job.

Book a Diamond Masterclass Deluxe

Would you like to learn more about the craft of diamond polishing? Book a Diamond Masterclass at Royal Coster Diamonds. In this Masterclass, one of my esteemed colleagues or I tell you everything about the craft. But you also get to polish a real diamond yourself. When the Masterclass is over, you get to keep this diamond as a precious memento. Last, but not least. All our diamonds at Royal Coster Diamonds are ethically sourced. So no war booty here. Besides the masterclass, we also offer (free) guided tours through our diamond polishing factory. In these tours, you get to see us working on the most beautiful diamonds. If you are looking for a diamond yourself, our diamond consultants are standing by to help you find the perfect piece.
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