Hoping to find some clues about what had facilitated Abraham’s accelerated progression, we searched online newspaper records.
Information about companies, partnerships and insolvencies in London can be found online in the London Gazette (see Related Links). Notices included in this publication can give information about a person or company's business activities, debts, creditors and addresses.
Esther searched online for her great-grandfather, Abraham Rantzen, and found that he appeared in the Court of Bankruptcy several times in the late 1860s.
This showed that he was clearly struggling as a businessman, so how could he have afforded to move to increasingly prosperous areas?
One of the later entries gave us our breakthrough. Esther spotted that he was now registered not as a cap maker, but as a diamond broker! This seemed to us to be a dramatic change in profession.
But to Esther, the rumour about a family connection to Barney Barnato, the famous 19th century diamond mine owner, started to sound increasingly likely.
Esther had always wondered why her father's middle name was Barnato. We now needed to investigate whether his parents had given him the name in a moment of optimistic aspiration, or whether there was a concrete connection with the Rantzen family.
Esther met historian Jerry Black, who had been researching the life of Barney Barnato to see whether there was any link to Esther's relatives.
Jerry revealed that Barney Barnato's real name was in fact Barnett Isaacs. Born in the East End, Barnett had changed his name as a young man when he joined the diamond rush to South Africa in the late 19th century, and he quickly went on to make millions from mining diamonds.
Barney had left behind a sister in the East End. Her name was Sarah Isaacs, who had married a local man - Abraham Rantzen!
So the famous diamond millionaire was in fact the brother-in-law of Esther's great-grandfather, the cap maker Abraham. This made him Esther's great-great-uncle Barney.
Now that she knew there was a genuine family connection, Esther wanted to find out what kind of relationship the Rantzen family had with Barney.
We also wanted to discover whether Barney's riches had had anything to do with Abraham Rantzen's social rise from Spitalfields cap maker to Paddington diamond broker.
We turned once again to the Probate Office to see whether it would help us to solve another of Esther’s family mysteries.
Wills can be very useful in yielding a lot of information about family relationships and the business activities of an individual. The Probate Office in Holborn holds wills proved since 1858 (see Related Links).
We had discovered that once he had arrived in South Africa with his brother, Barney had been fortunate in buying the right plots of land. He became one of the richest men of his age, and in 1888 was bought out by his chief rival the empire builder, Cecil Rhodes for £5.3 million – the equivalent of almost half a billion pounds today. At the time it was the biggest cheque ever written.
Barney was therefore a seriously wealthy man. If he had been an equally serious family man, there was every chance that he would have left some of his fortune to his sister, Sarah, and her family.
To find out for sure whether the Rantzens were left anything by Barney Barnato, Esther dug out his will at the Probate Office.
Barney's will revealed that on his death he did indeed leave substantial sums of money to his sister Sarah, her husband Abraham and their children. This money would have made a huge difference to the Rantzens' lives. In today's money, Abraham and Sarah received the equivalent of £50,000 a year, and her great-grandfather Hyam received the lump sum equivalent to £100,000.
This proved to Esther that Barnato had enabled Abraham's advancement from struggling cap maker in Spitalfields to flourishing diamond-broker in Paddington, and alsp supplied inspiration for the name of Abraham's grandson!
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