How do jewellers capture every last particle of gold dust?

An ingenious industry is turning workshop waste into profit
All that litters: Gary Williams of Mastermelt presides over the burning of commercial waste © Charlie Bibby

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In a basement on London’s Hatton Garden, a small production team is heating a furnace to 2,000C — a temperature that will obliterate most materials placed within it. Each day, here at precious metals refiner Mastermelt, the furnace is fed a diet of objects collected from jewellers’ workshops — full bags from vacuum cleaners, used wet wipes, blunted sandpaper and even old carpets — in the hope that when the ashes are processed, thousands of pounds’ worth of gold, platinum and more will remain.

“We always tell people, don’t throw anything away,” says Gary Williams, a director at Mastermelt, who the previous week paid out £17,000 to a jeweller who had been casually stockpiling the general detritus a workshop produces. “He’d just been saving all this stuff and didn’t realise what it was worth.” Mastermelt makes its money by taking a commission on the value of the scrap metal refined, as well as charging for processing.

Part of Mr Williams’ job is to educate jewellers on the financial rewards of hoarding every waste-attracting object and sending the haul — known as a sweep — to a refiner to be melted down and the precious metals reclaimed. Most jewellers will be astute enough to collect hard scrap, also known as lemel, which includes filings caught in animal skins hung beneath workbenches for this very reason, or clippings from claws cut to size when setting a diamond in a ring. Once weighed, the value of this scrap can be easily ascertained, and Mastermelt has an app that can be downloaded to give jewellers access to live prices.

The transformation of the residue into molten gold © Charlie Bibby

But the precious metal they cannot see may bring in surprising amounts of money too. The grinding, filing and buffing required to create jewels by hand or machine send microscopic clouds of precious dust into the air; the dust can land anywhere and be easily transported as it sticks to shoes and clothing. “We went to a workshop in Birmingham and right at the front of the building was a big 4ft sq coconut mat,” says Mr Williams. “Every single person coming in and out of the building walked over that mat, and had been doing so for seven or eight years.

“They didn’t think it was worth anything as it wasn’t in the workshop, but they let me take it away. We swept up the dirt and processed it and it came to quite a few thousand pounds.” Another surprise source was a pair of chair covers from a shop in Hatton Garden which were so choked with platinum dust that Mastermelt paid out £3,000 after processing them.

Mr Williams has a vault of stories about reclamation and its valuable surprises, but most of them are kept inside the trade. “People don’t really like it being talked about as this is their Christmas bonus,” he says. “Whatever money you make from reclamation is cash flow for your business. It’s found money.”

Timing is important in making sure a reclamation is as profitable as possible. First, a jeweller must ensure they have accumulated a large enough sweep to make a profit. Stuart Wibberley, sales director at Cooksongold, another refiner, says processing carries a flat fee of about £300 “whether you have 30 bags or 300”. (Mastermelt says its fees are variable, typically about £4 per kilo processed.) Then there are metal prices: Mr Williams says Mastermelt was “inundated” after the vote for Brexit in June, when the gold price spiked from $1,265 per oz the day before to $1,316 per oz the day after.

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The transformation of the residue into molten gold © Charlie Bibby

Reclaiming precious metal waste has always been a cornerstone of a jewellery workshop’s routine, but the practice has rarely been as sophisticated as it is today. “It really was considered a bonus in the trade,” says Mark Brittain, whose family business, Brittains Marking, creates complex tools for the luxury jewellery industry.

He ran the company, which was founded in 1850, from the 1970s until the early 2000s, when he retired from the jewellery trade. He now operates a commercial property business in Birmingham.

Mr Brittain recalls old-fashioned sweet jars being filled with tiny coils of metal, a byproduct of engraving cufflinks. The owner of one particular London jeweller that Brittains Marking worked with in the 1980s kept all the engraving scraps that were not requested by customers — Mr Brittain says some clients were indeed savvy enough to ask for theirs back — and cashed it in once a year to fund a cruise aboard the QE2 luxury liner.

This was during what some in the trade call “the Brylcreem days”. Jewellery workers were said to slather their hair with that pomade so that they could run their hands, covered in precious metal dust, through it, later retrieving the gold or silver. Mr Brittain has stories of such practices, and Winchester jeweller Jeremy France, whose twice-yearly sweeps at the workshop in his store yield between £6,000 and £8,000 a time, jokingly refers to an industry expression that “we don’t employ people with sweaty hands or turned-up trousers,” both ideal for accumulating valuable dust.

Four flights above the jewellery boutique of David Morris on Bond Street, polisher Dave Wadeson, who has been in the business for 40 years, says he once saw floorboards glittering in a workshop when he was an apprentice.

“When [the workshop] was taken over by Bentley & Skinner, they took up all the floorboards and the amount of lemel embedded in them was incredible — they found piles of fine grain around the edges,” he says.

When Mr Williams worked at wedding ring manufacturer Brown & Newirth, the business moved workshops around 1990 and dismantled its five-storey wooden staircase, which was so impregnated with precious metal that it looked like the “glitter in a marble kitchen top”. It turned out to be worth tens of thousands of pounds — enough to pay for a new staircase and the workshop’s moving costs.

And at Cooksongold, which claims to be the UK’s largest precious metals refiner, processing 25,000 jobs a year, Mr Wibberley recalls when a parquet floor in its own factory was ripped up and the precious metals embedded in the wood made it worth £20 per sq m.

Large jobs like burning floorboards, carpets or benches tend to happen when a jeweller is moving premises or upgrading. There are less extreme options for the interim, such as specialist vacuuming services or sanding down the top layer of benches and processing the wood dust. The challenge is picking up the day-to-day waste, and it is an art that is being constantly refined — particularly by larger manufacturers with the most to gain.

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At Hockley Mint, sweepings are turned into gold nuggets © Edward Moss

New technology being introduced to these factories is actually increasing waste, requiring even greater efforts to capture it. One British jewellery manufacturer, which did not wish to be named, has invested in sealed milling machines fitted with vacuums to capture the coils and swarf (sawdust-like chips of precious metal) they dispatch at high speeds. Each has a filter that can separate materials as thin as a micron — much narrower than a human hair.

In Birmingham’s Jewellery Quarter is Hockley Mint, a British jewellery manufacturer with a turnover of £12m that produces up to 140,000 pieces a year. Gathering scrap and lemel at its 30,000 sq ft factory requires daily cleaning and collecting, as well as the use of localised vacuums. “One of the things we have put in place that is relatively new is that when workers wash their hands we save the paper towels they dry with,” says managing director Gary Wroe.

“We got £2,000 back in a 12-month period just from the towels, and that goes straight on our bottom line.”

Gary Wroe MBA Managing Director of Hockley Mint, Birmingham © Edward Moss

Hockley Mint has also upgraded its windows so that blinds are now encased between panes of glass — their fabric panels were a magnet for precious metal dust — and it also has an on-site laundry to process workers’ clothes.

Its biggest investment in precious metal reclamation to date has been an incinerator, which it installed 18 months ago, to melt, but not process, its sweeps. “If you send a bag of material out, you don’t know what’s coming back,” says Mr Wroe, who adds that the value of precious metals it is collecting has increased since taking over its own incinerating.

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His concern is one shared by many in the industry. Looking at the accumulation of sludge from settlement tanks placed beneath sinks, grimy mop heads and all manner of other dirt and waste collected in a sweep, it is impossible to estimate how much money has accrued, although there are ways to guess.

Jewellers expect to lose metal during the production phase and so will plan for it. At David Morris, the target is a maximum loss of 5 per cent, although its craftsmen believe the working figure is 1 per cent or 2 per cent, providing a guide for what could be reclaimed.

Stephen Redshaw hoovers up the filings for recycling at Hockley Mint, Birmingham. © Edward Moss

Hockley Mint uses scales to give as accurate a forecast as possible. “We measure in and measure out, and keep records so we know approximately what we should get back,” says Mr Wroe.

For others, guesstimates are based on experience, and this can lead to friction between jeweller and refiner when discrepancies arise. “Some people have expectations based on history but they haven’t got a complete understanding of what’s going on,” says Mr Williams. The gold price might have changed, he suggests, or the weight of material being processed could be similar but the contents disparate. “In this industry, trust is a big factor,” he says.

But that trust goes both ways. Sweeps can take weeks to process and refiners will sometimes advance money based on the expected yield, which can give less scrupulous jewellers an opportunity to run a ruse. “I heard a story about a sweep where the processor took the job, gave the customer an advance based on history and when they looked in the sweep bag, the bottom of it was newspapers,” says Mr Williams.

Cooksongold offers its clients advances at its trade counters in London and Birmingham. The business is part of the German Heimerle + Meule group and much of its refining is done at the group’s plants in Spain and Germany. This adds to the processing time, so it will do a pre-melt in London to ascertain what it is sending to Heimerle + Meule.

Processing its own pre-melted metal would be the next stage in Hockley Mint’s reclamation journey, but it is one that Mr Wroe has yet to commit to. “That’s a different skill and we’d have to bring the expertise in, so we’d have to work out whether it would be worth it.”

While Mr Wroe’s approach to reclamation is far more advanced than many other workshops, he is nonetheless resigned to the fact that he will never catch it all. “We have sticky mats at the doors to get the dust off people’s shoes as they leave the building, otherwise the streets of Hockley would be paved with gold,” he sighs. “And the council should definitely check the sewers.”

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