Synthetic diamonds are produced using high-tech processes, but is it possible to grow them with no specialised equipment? My father claimed that this was so.
The tale takes place in the 1920s or 30s, during which time he had jobs in Johannesburg and in Durban. Someone had a diamond ring with the stone working loose from the clasp, and somehow he was the one who took it to a jeweller for securing.
He was told to collect it some days later, and when he was given the ring he glanced at it and thought he saw a speck inside the stone. He looked more closely and was now sure that he could see an inclusion, yet he could remember looking at it before and admiring that fact that it was completely clear.
So, he pointed this out to the jeweller who seemed to go into a bit of a flap. He didn’t think there was an inclusion, but wait, he’d go back into his workshop where he could take a good look. He vanished around the back and meanwhile his wife, who helped out there, had suddenly come in and began chatting to Dad in a very friendly manner.
Soon the jeweller returned and said no, he had cleaned it and could see no inclusion. It must just have been some dirt on the back of the stone – here, look with a magnifying glass. All now seemed well and so Dad left, with the ring.
Later he mentioned this to a friend in the jewellery trade, and the fellow laughed at the story. He explained that a less-than-honest jeweller would start off with a small diamond of his own, say 0.37 carats. When a ring came in for some work, such as re-setting the stone, he would check the weight. Say it was 0.40 carats, he would switch it for his smaller stone and could be fairly sure that the sizes were so close that the owner wouldn’t notice.
A month later a ring that came in would have a 0.45 carat stone and he would switch it for his that was now 0.40 carats, and a few weeks later that would go in place of a diamond of 0.48. Before long he would have a diamond of a full carat or so, worth far more than the tiny one with which he started. That was why this trick was referred to in the trade as “growing a diamond”.
Obviously this is a form of theft against each of the unlucky owners and that was the reason for the panic when Dad noticed something. Back in the workshop the scheming jeweller had quickly replaced the original and his wife, who was in on the scam, played her part of trying to distract him.
Most diamonds in rings are white, and although there are subtle differences that are important to diamond traders they are generally not obvious to the average owner. Also, virtually all diamonds in modern times are cut to the same “brilliant” pattern and so one looks much like the next. Thus the victim will not normally notice, and it was just that the jeweller got careless on this occasion when he replaced a flawless stone with one that had an inclusion.
When the jeweller dashed back to the workshop, might he just have replaced it with another impostor but taken more care to find one with no inclusion? Personally, I think it unlikely. For all he knew the owner could have some documentation with a record of the correct weight, and with suspicions already raised that might have been checked later.