Four diamonds on the dial. Not four thousand on the invoice.
Certified lab-grown diamonds — the same carbon, the same hardness, the same fire as mined stones. Set into the watch shape everyone recognises.
A diamond is carbon in a lattice. Ours is too.
- Stones 4 per dial, set at the hour markers
- Type Lab-grown diamond (crystalline carbon)
- Hardness 10 on the Mohs scale — the hardest material used in jewellery
- Cut TODO — confirm cut with supplier before launch
- Carat weight TODO — total carat weight per dial
- Colour / clarity TODO — grade range, or delete this row
- Certification Certified by internationally recognised gemological laboratories
The questions people actually have about lab-grown diamonds.
Answered plainly, because the answers are good.
Is it a real diamond, or a fake one?
It is a real diamond. Chemically, physically and optically identical to a mined diamond — the same atomic carbon structure, the same refractive index, the same 10 on the Mohs scale. It is not cubic zirconia and it is not glass. Those are different materials entirely.
Can anyone tell by looking?
No. A trained gemologist cannot separate lab-grown from mined by eye either — it takes specialist equipment reading trace growth patterns. On a wrist, in a room, across a table, there is nothing to see.
Then why is it so much cheaper?
Because growing carbon in a reactor takes weeks, and finding it under a continent takes decades of mining, hauling and sorting. You are not paying less for a lesser stone. You are paying less for a shorter, cleaner supply chain — no destructive mining, no conflict sourcing.
Will it hold its value?
Be careful with anyone who promises you that about any watch under $1,000. Lab-grown diamonds are not an investment asset, and neither is a quartz dress watch. Buy this because you want to wear it every day for years, not because you expect to resell it.
Will it scratch or cloud over time?
No. Hardness is a property of the material, not its origin. At 10 on the Mohs scale, effectively nothing in daily life scratches it — which is exactly why the crystal above it is sapphire, second only to diamond.
Every stone Berlo sets arrives with certification from an internationally recognised gemological laboratory, confirming origin, clarity and cut.
Same shape. Same stones, in the ways that matter.
Cartier prices are publicly listed starting prices, verified 09.09.2026. Cartier is not affiliated with Berlo.
What are you paying for — the stone, or the name above it?
Four diamond-set colourways.
One silhouette, four finishes. Each dial carries the same four stones.
Prefer a plain dial? Eight non-diamond colourways start at €260.
The watch under the diamonds.
A diamond dial is only worth setting into a watch that deserves it.
Swiss Ronda 762
A genuine Swiss movement from Ronda, making movements in Switzerland since 1946. Rated up to ten years of battery life.
Sapphire crystal
Scratch-resistant sapphire — 9 on the Mohs scale, second only to the diamonds beneath it.
Recycled 316L stainless steel
Waterproof, hypoallergenic, and it will not tarnish. Solid steel, not a lighter plated alloy.
36 mm case, unisex
Enough presence to be noticed, slim enough to keep the proportions the shape depends on.
Signature blue crown
The detail the original has carried since 1917, in the same position.
Quick-release cactus leather strap
Plant-based leather, handcrafted in Ubrique, Spain. Swap it in about twenty seconds, no tools. A second strap is included.
A shape borrowed from a battlefield.
In 1917 Louis Cartier looked at the tanks moving through the war and saw a shape: straight lines, a strong rectangle, nothing soft about it. He built a watch around it and called it the Tank. More than a century later the shape still looks right.
We did not invent this shape. Cartier did, and they deserve the credit. We believe great design can inspire more than one watch — so we built our own take on it, and put real stones in it at a price you can actually justify.
What people notice first.
“I was worried the rectangular case might look too small on my wrist, but the size is honestly perfect. It feels classy without looking tiny or overly delicate.”
“This watch looks even better in real life. The shape is timeless, and the whole thing feels way more premium than the price suggests.”
“I wanted something I could wear to work but also with jeans and a T-shirt. This somehow works with everything.”
“I compared so many rectangular watches before buying this one. For the design, sapphire crystal and Swiss movement, the price is kind of crazy.”
“I normally only wear round watches, so this was outside my comfort zone. Now it’s probably the watch I reach for most often.”
“The dial is clean, simple and very easy to read. It gives that quiet-luxury look without trying too hard.”
“The stainless-steel case feels solid and really well finished. Someone at work thought it was a Cartier, and they genuinely didn’t believe it was under $300.”
“The sapphire crystal was a huge selling point for me. You don’t usually see materials like this on watches at this price.”
“The blue crown is such a cool little detail. It’s subtle, but it makes the watch feel much more distinctive.”
“The proportions are spot on. It has enough presence to get noticed but never feels bulky on the wrist.”
“The silver version is super clean and easy to style. It works with basically everything in my wardrobe.”
“I’ve been wearing it regularly, and the sapphire crystal still looks great. It handles normal everyday use much better than I expected.”
“I had never tried a cactus-leather strap before, but it feels surprisingly premium. You honestly wouldn’t guess it was plant-based just by looking at it.”
“The strap was a little firm at first, but it softened up quickly. After a few wears, it started fitting my wrist really nicely.”
“The strap keeps the watch in place without feeling too tight. I’m not constantly adjusting it like some of my other watches.”
“The strap and case colours work so well together. The whole watch feels intentional and really well styled.”
“The strap stays comfortable even after hours of wear. No irritation, no stiffness and no need to take it off halfway through the day.”
“The fact that it has a Swiss movement at this price is seriously impressive. It has kept time perfectly since I received it.”
“Setting the time was quick, and the crown feels secure and well made. Nothing about it feels cheap or flimsy.”
“This is the kind of watch you can put on and forget about. It looks great, keeps time and doesn’t need any extra attention.”
“It has a nice weight to it without feeling heavy. You can tell you’re wearing a proper watch, but it’s still comfortable all day.”
Fair questions, answered.
Are the diamonds real?
Yes — real diamonds, grown in a laboratory rather than mined. Same carbon structure, same hardness, same brilliance, certified by an internationally recognised gemological laboratory. They are not simulants like cubic zirconia or moissanite.
Why does a diamond watch cost this little?
Two reasons. The stones are lab-grown, which removes the cost of mining. And there is no boutique, no ambassador contract and no century of advertising folded into the price. You are paying for materials and assembly.
Is it just a cheap copy of the Cartier Tank?
It is our own watch built on a shape Cartier introduced in 1917, and we say so openly. Same silhouette, same signature crown, sapphire crystal, Swiss movement, solid 316L steel. Where we differ from the diamond-set Cartier is the origin of the stones and roughly $19,700.
Will the stones fall out?
They are set into the dial, under sapphire crystal, sealed inside the case — not exposed on the outside of the watch. Every Berlo comes with a 24-month international warranty.
Isn't quartz a cheap movement?
The comparable Cartier Tank Must uses quartz too. Ours is a Ronda 762, from a Swiss movement maker operating since 1946, rated for up to ten years of battery life. What matters is which movement, not which mechanism.
What if I don't love it?
Thirty-day returns, no complicated process. Free worldwide shipping both ways, duties included.
One batch. Numbered on the case back.
We made 500 Berlo Tanks in this run. Not 5,000. Every watch carries its own collection number engraved on the back. When the batch is gone, this exact run is gone.
Real diamonds. Honest price.
Shop the Tank collectionFree worldwide shipping, duties included · 2-year international warranty · 30-day returns