Urban Sterling

Urban Sterling Mason Mignanelli • Conceptual jeweller. Narrative-driven silver and gold work. Newcastle studio open, DM for appointments. Read my book ↓

A Hollow ManOxidised satin intaglio relief with bright cuts for contrast. Inspired by The Hollow Men by T. S. Elliot and...
10/09/2026

A Hollow Man

Oxidised satin intaglio relief with bright cuts for contrast. Inspired by The Hollow Men by T. S. Elliot and released on the poem’s 100 year anniversary.

09/09/2026

As I mentioned in the video, De Beers literally built their own artillery piece during the Siege of Kimberley. The cannon was nicknamed “Long Cecil” in honour of Cecil Rhodes, who was actually trapped inside the town during the siege. Because the town lacked heavy defensive weapons, a De Beers mechanical engineer designed the gun, and the company’s tradesmen manufactured it in the diamond mine’s workshops in just 24 days. It was capable of firing 28-pound shells at the besieging forces.

It highlights how blurred the lines were between the De Beers diamond monopoly and the British colonial military apparatus. The immense wealth generated from the Kimberley mine, which remains one of the largest hand dug excavations in human history financed a corporate militia that literally redrew the map of the continent.

03/09/2026

The resale market for diamonds is very harsh for the consumer. The diamond industry trades stones based on wholesale pricing grids, like the Rapaport Diamond Report, which are divorced from the retail prices you see in shop windows. When you try to sell a diamond back to the trade, you’re competing against an efficient global supply chain where jewellers can buy exactly what they need on demand.

Furthermore, the explosion of lab grown diamonds has shattered the illusion of scarcity. Lab grown stones are chemically, physically, and optically identical to natural ones, but they can be manufactured endlessly. You should buy a diamond because you love how it handles light and because its physical toughness means it will survive decades of daily wear on your hand, not because you think you can cash it in later.

01/09/2026

Sapphire doesn’t have diamond’s weak cleavage planes, which means it doesn’t share the same directional vulnerability to impact. But corundum has its own little secret: parting.

Corundum has no true cleavage, but natural sapphires can contain repeated twin lamellae, which are structural boundaries in the crystal often produced by deformation after growth. In heavily twinned* material, those planes can become directions of weakness, allowing the stone to break along surprisingly clean, flat surfaces that look a lot like cleavage.

Hence the other name for it: false cleavage.

Significant parting isn’t something you expect from every clean gem sapphire, but it’s an interesting phenomenon

* twinning is when a crystal contains multiple regions whose atomic structures are arranged in precise, symmetrical but different orientations. Imagine the crystallographic pattern basically flipping at certain points

28/08/2026

Cecil Rhodes conquered over a million square kilometres of land using his private corporate army. But his ambition didn’t end with territorial conquest.

When Rhodes died in 1902 at just 48 years old, his will directed a large portion of his De Beers diamond fortune into creating the Rhodes Scholarship at the University of Oxford.

His goal was to fund the education of top students from across the English speaking world so they would return home, enter politics, and champion British imperial ideals.

For over a century, that diamond money funded future presidents, prime ministers, and global leaders (including Bill Clinton and Bob Hawke). But it also sparked the massive, worldwide “Rhodes Must Fall” movement, where modern students protested the prominent statues of Rhodes standing over the very university buildings his corporate diamond conquest paid for.

25/08/2026

Aluminium oxide is also known as corundum or emery. It is the abrasive grit glued onto sandpaper, sanding sticks, and grinding wheels. Because it sits at a 9 on the Mohs hardness scale, corundum cuts, carves, and scratches everything beneath it.

Which leads to a strict hygiene rule at my bench: gemstones rated Mohs 9 and below have to be completely quarantined from sandpaper particles.

If loose grit from a piece of sandpaper drifts across my workspace, settles in a polishing mop, or gets onto a stone tray, it can ruin a stone. If that rogue corundum dust rubs against an emerald (Mohs 7.5–8), a piece of quartz (Mohs 7), or even the polished facets of another sapphire, it will gouge the stone’s mirror finish.

21/08/2026

As I mentioned in the video, the logistics of building a weapon inside besieged Kimberley were really absurd. George Labram didn’t even have proper gun steel, so he machined Long Cecil from a huge billet of mild steel originally intended as shafting for De Beers’ industrial machinery. Labram compensated by shrinking reinforcing iron hoops around the barrel. They even cast their own explosive shells in the company’s workshops, literally marking them “DE BEERS” with a diamond logo as if they were pieces of corporate merchandise. Some were even engraved with “with compliments, Cecil John Rhodes”.

Then the Boers brought in a huge French made 155mm “Long Tom.” (Why are they all so long?). One of its shells struck Labram’s hotel room and killed him. His funeral was held after dark for safety, and the Boers still shelled both the procession and the cemetery during his burial. It’s a bizarre reminder of how far removed the early diamond industry was from the romantic image De Beers would eventually create around itself.

13/08/2026

I mentioned that a lot of jewellers will just take a Pinterest board and build whatever is on the page. A massive reason for this trend is the rise of computer aided design.

When a custom jeweller designs a ring on a screen, 3D software makes paper thin metal look flawless. On a monitor, a 1mm band looks perfectly rigid and very clean. But CAD software exists in a digital vacuum. Pixels don’t experience metal fatigue. Pixels don’t grip heavy steering wheels, pull open jammed doors, or carry shopping bags.

When you translate digital models directly into gold without adjusting for real world physics, you’re making a delicate sculpture that will collapse under everyday wear.

07/08/2026

I mentioned in the video that King Edward I mandated gold testing in 1300. But without modern spectrometer guns or X-ray testers, how did medieval assayers actually test gold purity at Goldsmiths’ Hall?

They relied on a clever combination of a dark stone and acid, known as the “touchstone method.”
An assayer would take a gold ring and rub it across a flat piece of black, fine grained stone (touchstone) to leave a metallic streak. Next to it, they would make a second streak using a “touch needle”, which was a reference strip of gold with a known, exact purity. They would then pour a drop of nitric acid across both streaks.

If the ring was fake or diluted with cheap copper, the acid would quickly dissolve the streak away. If it was true high carat gold, the streak remained completely untouched. It was simple, non destructive chemistry that held the entire economy together for centuries.

03/08/2026

Two chemists independently figured out how to extract aluminium using electricity in 1886. But the sheer coincidence of this event is nuts.

In 1886, an American named Charles Martin Hall and a Frenchman named Paul Héroult were both 22 years old. Working thousands of miles apart, with zero communication, they both independently realized that if you dissolve aluminium ore in a bath of molten cryolite and pass a high electrical current through it, pure aluminium separates out effortlessly.

Not only were they the exact same age when they made the identical discovery, but they were also born in the exact same year (1863) and died in the exact same year (1914). Their simultaneous discoveries gave birth to the modern Hall-Héroult process, permanently transforming a precious metal into an industrial commodity basically overnight.

Address

39a Beaumont Street
Newcastle, NSW
2303

Website

Alerts

Be the first to know and let us send you an email when Urban Sterling posts news and promotions. Your email address will not be used for any other purpose, and you can unsubscribe at any time.

Shortcuts

Share

Category