Truly unique · Black zirconium
One diamond, black
From £475
A single ten point diamond, flush set into black.
One round diamond of a tenth of a carat, set level with a domed black zirconium band. Against black oxide a white stone reads far brighter than it would in any white metal, which is why one is enough.
Made to order · 2 to 3 weeks · posted insured
Before you order, in one place
- What you are buying
- One diamond, black, black zirconium, made to order in your size. Widths 4 to 10mm.
- Price
- £475 total. UK delivery and engraving are included and nothing is added at checkout.
- When it arrives
- 2 to 3 weeks to make, then one working day insured and signed for. Delivery in full
- Changing your mind
- 30 days from delivery, return postage paid, unless you have it engraved. The cancellation right
- Who you are contracting with
- Trothe Ltd, registered in England and Wales, company number 17431230, Lytchett House, 13 Freeland Park, Wareham Road, Poole, Dorset, BH16 6FA. Questions and complaints to hello@trothe.co.uk.
- MaterialBlack zirconium
- Surface hardnessMohs 8
- Density6.5 g/cm³
- ResizableSpecialist assessment
- HallmarkedNot applicable, non precious
- MadeTo order, in your size
- Delivery2 to 3 weeks, insured
- Returns30 days, unengraved
- EngravingOptional, included, inside the band
- StoneSingle diamond, 0.1ct, Mohs 10
Also in: Wedding rings, His and hers, Men's rings, Women's rings
About this ring
One diamond, black, in detail
One round diamond of a tenth of a carat, set flush into a domed band of satin black zirconium, and nothing else. The black works like a jeweller's velvet: against it, a white stone reads far brighter than it would in any pale metal, so a single diamond carries the whole ring. The dome lets light slide across the satin oxide and keeps the profile soft. At 0.1 of a carat the stone is more than three times the carat weight of the single diamond on Diamond set, titanium, and on black it looks larger still.
How it wears
The oxide surface of black zirconium is hard, typically around Mohs 8, and resists the light knocks of everyday wear; a severe blow against something abrasive can expose the lighter metal beneath. The diamond is Mohs 10 and set level with the surface, so it is neither proud enough to catch nor open to a sideways knock. If a pale mark ever appears on the black, it can be transferred metal lying on top rather than damage. The ring is hypoallergenic.
Choosing yours
A single stone of this size is a clear statement on black, so width decides how bold the whole ring feels. At 4 or 5mm the diamond fills much of the band and the ring reads as fine jewellery; at 8 to 10mm there is a broad field of black around it and the effect is graphic and spare. It suits someone who likes black but wants one point of light. It pairs with itself, and for more stones, Three diamonds, black and Scattered set take the same idea further.
Width by width
| Width | How it reads | Weight, est. | Price |
|---|---|---|---|
| 4mm | Slim, the quietest everyday width | 2.1g | £475 |
| 5mm | Between slim and classic | 2.6g | £475 |
| 6mm | Classic, the usual starting point for a band | 3.2g | £475 |
| 7mm | Classic to broad, more of the pattern shows | 3.7g | £475 |
| 8mm | Broad, a ring that is clearly there | 4.2g | £500 |
| 9mm | Wide and bold, best on a larger hand | 4.7g | £500 |
| 10mm | Wide and bold, best on a larger hand | 5.3g | £500 |
Weights are estimates for a plain band of the same width in black zirconium at UK size N with a 1.6mm wall, from the model in our ring weight calculator. A pattern cut into the surface removes a little metal, so the finished ring is slightly lighter. The price steps up at the widths that take more metal to make.
How it compares with the rings nearest it
| Ring | What sets it apart | Metal | Widths | Surface hardness | From |
|---|---|---|---|---|---|
| One diamond, black (this ring) | A single ten point diamond, flush set into black. | Black zirconium | 4 to 10mm | Mohs 8 | £475 |
| Tyre tread, black | A tyre tread, cut around a black zirconium band. | Black zirconium | 4 to 10mm | Mohs 8 | £449 |
| Claddagh, black | The claddagh, hands, heart and crown, cut into black. | Black zirconium | 4 to 10mm | Mohs 8 | £449 |
| Celtic, black | A continuous Celtic knot, cut into black zirconium. | Black zirconium | 4 to 10mm | Mohs 8 | £449 |
There are 17 black zirconium bands in the range, from £199 to £625. All about black zirconium.
The metal, in brief
Heating zirconium forms a black ceramic oxide at its surface. The colour comes from that oxide, rather than applied black plating. It is a hard surface over a softer metal core, so scratch resistance does not mean the whole ring is black or immune to damage.
Surface hardness Mohs 8, density 6.5 g/cm³, and hypoallergenic, so it is a sound choice for skin that reacts to nickel. It is not a precious metal, so it carries no hallmark.
Compared side by side: Anodised zirconium or black zirconium, Black zirconium or titanium, Black zirconium or sterling silver. Or read the full black zirconium guide.
Work it out before you order
About One diamond, black
- Can this ring be resized?
- Black zirconium needs specialist assessment. GETi describes resizing as difficult and time consuming, rather than completely impossible. The oxide surface, construction and requested size change need consideration. Do not assume a local jeweller can alter it or that a replacement is automatic. Ask whether the proposed solution alters the original band or supplies a remake, and confirm the finish, engraving, cost and timing.
- Is engraving included?
- Yes, and it is optional. Leave the box blank and the ring is made plain. If you do want one it is laser cut inside the band where the ring is made, rather than sent out to a third party, and there is no charge and no extra wait.
- How long will it take?
- 2 to 3 weeks. It is made in your size after you order, not picked off a shelf, and that is the reason the widths and finishes are open choices.
- Can I return it if I have it engraved?
- Not for a change of mind. An engraving makes the ring clearly personalised, which puts it outside the statutory right to cancel, and it cannot be resold. Every ring shop draws the line here. Order it plain and you keep the full 30 days. Either way, a ring that arrives faulty or is not what you ordered is covered by the Consumer Rights Act, which nothing waives.
- How much does the One diamond, black ring weigh?
- About 2.1g at 4mm, 3.2g at 6mm, 5.3g at 10mm, estimated for a plain band in black zirconium at UK size N. Larger sizes and wider bands weigh more. It is a light ring by any standard: 18ct gold of the same size is more than twice the weight.
- What widths does it come in, and do they cost the same?
- 4 to 10mm. 4mm, 5mm, 6mm, 7mm are £475, and 8mm, 9mm, 10mm £500, because the wider bands take more metal to make.
- What is closest to the One diamond, black in the range?
- Tyre tread, black (black zirconium) and Claddagh, black (black zirconium). The comparison table on this page sets them side by side on metal, width, hardness and price.
- What if I get the size wrong?
- If it is unengraved, return it inside 30 days and we refund it, and we pay the postage. Use the free ring size finder first if you are unsure, and if the ring is a surprise, ask us and we will talk you through the ways to find out without asking them.