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Diamond Portraits: Johannes Jacobus Jonker & Johannes Makani

Diamond Portraits: Johannes Jacobus Jonker & Johannes Makani

We have written about the Jonker diamond and some of its history a number of times. Yet parts of the story of this diamond were virtually never discussed. The 726-carat Jonker Diamond was reportedly found in South Africa on January 17, 1934 by Johannes Jacobus Jonker. One of the biggest rough diamonds ever discovered, it was originally sold for £75,000.

Harry Winston purchased the diamond from De Beers in 1935 for $700,000. It was one of his most important purchases, because it helped Winston build his name as a leading diamond jewelry maker. When Winston tried to insure the diamond, he found that due to its high value, he could not find anyone willing to insure it. When it was time to ship it from South Africa to the US for polishing, he eventually decided to do it in a surprising way: in a plain unmarked envelope in the regular mail, at a cost of $0.64.

To generate publicity, Winston put the rough diamond on display at the American Museum of Natural History and took it on a tour, having it photographed with a number of Hollywood stars, including Claudette Colbert and Shirley Temple. When he decided to polish the diamond, Winston commissioned Lazare Kaplan to cleave it. 

In 1936, Winston gave the diamond to Lazare Kaplan to be polished. Although his company, Lazare Kaplan & Sons, was already a well-established diamond polishing and trading company, getting the 726-carat Jonker diamond to work on propelled his reputation even further. The fee, enormous for depression era times, was reported to be $30,000.

Initially, Kaplan accepted the job from a competitor, because he wanted his son to gain experience. However, upon examining the diamond, he concluded that the suggested way to cleave it would cause the diamond to shatter. He studied the diamond for a year together with his son. They built models of the diamond and considered various ways of cutting it. On April 27, 1936, Kaplan made the first cut, cleaving off a 35-carat section. At the end of the process, the rough diamond was polished into 13 diamonds. The largest was named Jonker I, a 142.90-carat, emerald-shaped, D color, and flawless clarity diamond. The other diamonds polished from the original rough ranged in weight from 40.6 to 3.53-carats. It was the first major rough diamond to be cut in the United States.

The Jonker diamonds went on to become highly sought-after items, and today, their legacy gives them a historic status. But what is the origin of this stone?

Johannes Jacobus Jonker was a poor man who kept looking for his fortune, with no luck. A father of seven, he lived a difficult life. Like many Afrikaners in South Africa at the time, he hoped to strike it rich by digging for valuable resources. The time of great finds in the region was already behind him, and he resorted to being a digger.

Diggers were individuals who quite literally dug in the ground, square meter after square meter, in the hope of discovering that something valuable. It was a physically difficult, financially unrewarding way of life for most people.

In early 1934, Jonker was exploring a small claim by the Elandsfontein, about 5 km south of the Premier mine in South Africa. He lived nearby with his wife and at least two of his sons. He also employed two local men, native South Africans. One of them was Johannes Makani.

On January 17, 1934, Jonker did not want to get out into the windy and unfriendly environment to work. As the story goes, he sent his son with Makani to their claim. Makani was working on tailings, washing away the dirt, when he noticed a rather large stone, covered with a thick layer of dirt, but had a small area shining. He cleaned it further to realize that he was holding an exceptionally large diamond.

Jonker’s son Gert, thought he was looking at a piece of glass, but rushed to show it to his father. The 62 year-old Jonker gave the stone to his wife for safe keeping. Mrs. Jonker apparently slept with the stone around her neck wrapped in a stocking, while her sons stood guard outside their cabin with revolvers. The fame and fortune that this stone would bring Mr. Jonker was short-lived. His windfall of £75,000 did not last long, and he lived the rest of his life a poor man.

There is no record of Makani, the real finder of the diamond, ever being rewarded for his exceptional find.

The Jonker I was purchased by King Farouk of Egypt in 1949, but the whereabouts of the diamond became a mystery after the king was deposed and exiled in 1952. It reappeared some years later, and the new owner of the diamond was Queen Ratna of Nepal. The last known transaction of the Jonker I diamond was in 1977, when the diamond was sold privately in Hong Kong for $2,259,000 to an anonymous buyer. It is believed that the same anonymous buyer still owns the diamond today. 

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