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![Old-cut round lab diamond carat size comparison on the hand [ld all]](http://luthersdiamonds.com/cdn/shop/files/7A057DCB-D7CF-4CAC-AFAC-840A8304F141.png?v=1778817292&width=1080)
![Old-cut round lab diamond carat size comparison on the hand [ld all]](http://luthersdiamonds.com/cdn/shop/files/7A057DCB-D7CF-4CAC-AFAC-840A8304F141_1800x1800.png?v=1778817292)
The Marlowe
Handcrafted by our family workshop · Made to order
Vintage elegance, refined with restraint.
Read the story
An Old European-cut diamond sits within a delicate milgrain bezel, highlighting the stone’s soft facets and candlelit brilliance with a silhouette that feels both antique and timeless.
Clean cathedral shoulders rise toward the center, accented by subtle side diamonds that add just enough light without overwhelming the design.
Balanced, stackable, and quietly heirloom-inspired.
Drop a hint.
Send this one quietly to someone who should know.
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Before you order
Good to know
When will it arrive?
Hand-carved designs like this one usually arrive in 8–10 weeks, made to order and delivered with free insured shipping.
Have a proposal or wedding date? Tell us before you order and we'll confirm honestly whether we can make it.
How do I get my size right?
Please take a minute with it. Use our printable sizing guide at 100% scale, measure at the end of the day, and measure twice. Quarter sizes are fine, and we can work from US, EU or mm. We confirm your size with you before we start.
If your size ever changes, our family team will walk you through the options, but a ring built in your size from day one always wears best.
Engraving & Stone Inlay®: what's included?
Both are on us. Engraving: up to 9 characters, spaces included (like “J&A 2027”). Your handwriting is free too. A custom font or placement is $75, since it needs its own CAD.
Stone Inlay®: two small birthstones set into your band, often yours and theirs.
Will I see my diamond before it's set?
Yes, on every order. Within 24 hours we send a video of your exact diamond and its IGI report (DEF color, VS2+ clarity). Approve it, and that's the stone we set. Prefer natural? Request a natural diamond.
Is it ethically sourced?
Yes. Your diamond is lab-grown, never mined, and so is every accent diamond on this piece. You don't have to take our word for it:
- Your IGI report states “laboratory-grown” in writing.
- The report number is laser-inscribed on your diamond, so you can look it up on IGI's website and match it to your stone.
- Before we set it, we send you a video of that exact diamond.
Prefer a natural diamond? We source them only from suppliers whose invoices carry a Kimberley Process and System of Warranties statement. Request a natural diamond
Adding Stone Inlay®? Those birthstones vary: some are lab-grown and some are natural. Just ask about yours.
Can I return it?
You can cancel for a full refund before production starts. Once your piece is at the bench it's a final sale, since it's made to your exact choices. If it arrives damaged or has a craftsmanship issue, tell us within 14 days and we'll make it right.
More answers in our FAQ, or start a custom build.
Material
14K Solid Gold or Platinum 950
Main Stone
Diamond
Band Width
Stone
Built to Last. Backed for Life.
Every Luther's Diamonds ring is handcrafted in our Atlanta studio, using only the finest metals and ethically sourced stones. We stand behind our craftsmanship for life — if it leaves our studio, we stand behind it.
Ring Size Guide
US & Canada Ring Sizes
| US Size | Diameter (mm) | Circumference (mm) |
|---|---|---|
| 3 | 14.1 | 44.2 |
| 3.5 | 14.5 | 45.5 |
| 4 | 14.9 | 46.8 |
| 4.5 | 15.3 | 48.0 |
| 5 | 15.7 | 49.3 |
| 5.5 | 16.1 | 50.6 |
| 6 | 16.5 | 51.9 |
| 6.5 | 16.9 | 53.1 |
| 7 | 17.3 | 54.4 |
| 7.5 | 17.7 | 55.7 |
| 8 | 18.2 | 57.0 |
| 8.5 | 18.6 | 58.3 |
| 9 | 19.0 | 59.5 |
| 9.5 | 19.4 | 60.8 |
| 10 | 19.8 | 62.1 |
| 10.5 | 20.2 | 63.4 |
| 11 | 20.6 | 64.6 |
| 11.5 | 21.0 | 65.9 |
| 12 | 21.4 | 67.2 |
UK & Australia Ring Sizes
| UK Size | Diameter (mm) | Circumference (mm) |
|---|---|---|
| F | 14.1 | 44.2 |
| G | 14.5 | 45.5 |
| H | 14.9 | 46.8 |
| I | 15.3 | 48.0 |
| J | 15.7 | 49.3 |
| K | 16.1 | 50.6 |
| L | 16.5 | 51.9 |
| M | 16.9 | 53.1 |
| N | 17.3 | 54.4 |
| O | 17.7 | 55.7 |
| P | 18.2 | 57.0 |
| Q | 18.6 | 58.3 |
| R | 19.0 | 59.5 |
| S | 19.4 | 60.8 |
| T | 19.8 | 62.1 |
| U | 20.2 | 63.4 |
| V | 20.6 | 64.6 |
| W | 21.0 | 65.9 |
| X | 21.4 | 67.2 |
European Ring Sizes
| EU Size | Diameter (mm) | Circumference (mm) |
|---|---|---|
| 44 | 14.1 | 44.2 |
| 45 | 14.5 | 45.5 |
| 46 | 14.9 | 46.8 |
| 48 | 15.3 | 48.0 |
| 49 | 15.7 | 49.3 |
| 50 | 16.1 | 50.6 |
| 52 | 16.5 | 51.9 |
| 53 | 16.9 | 53.1 |
| 54 | 17.3 | 54.4 |
| 56 | 17.7 | 55.7 |
| 57 | 18.2 | 57.0 |
| 58 | 18.6 | 58.3 |
| 60 | 19.0 | 59.5 |
| 61 | 19.4 | 60.8 |
| 62 | 19.8 | 62.1 |
| 63 | 20.2 | 63.4 |
| 65 | 20.6 | 64.6 |
| 66 | 21.0 | 65.9 |
| 67 | 21.4 | 67.2 |
Japanese Ring Sizes
| JP Size | Diameter (mm) | Circumference (mm) |
|---|---|---|
| 4 | 14.5 | 45.5 |
| 5 | 14.9 | 46.8 |
| 6 | 15.3 | 48.0 |
| 7 | 15.7 | 49.3 |
| 8 | 16.1 | 50.6 |
| 9 | 16.5 | 51.9 |
| 10 | 16.9 | 53.1 |
| 11 | 17.3 | 54.4 |
| 12 | 17.7 | 55.7 |
| 13 | 18.2 | 57.0 |
| 14 | 18.6 | 58.3 |
| 15 | 19.0 | 59.5 |
| 16 | 19.4 | 60.8 |
| 17 | 19.8 | 62.1 |
| 18 | 20.2 | 63.4 |
| 19 | 20.6 | 64.6 |
| 20 | 21.0 | 65.9 |
| 21 | 21.4 | 67.2 |
Find Your Ring Size
Measure Your Finger
- Use a flexible measuring tape or length of string.
- Wrap it around the finger you'll wear your ring on. If you're creating a ring stack, consider where on your finger the ring will sit. If using string, mark the point on the string where the ends meet with a pen.
- Lay the string on a flat surface and use a ruler to measure the length (in inches or millimeters) up to the mark. Compare your measurement to the size chart to determine your ring size. If you are between sizes, opt for the larger size.
Measure an Existing Ring
- Choose a ring that already fits your finger well.
- Measure the interior diameter of the ring in millimeters (mm).
- Use the measurement chart to match the size of your ring to the closest size in mm. The interior of the ring should align with the outer edge of the circle.
Luther's At Your Service
There's no question too small or request too large for Luther's Diamonds client advisors. From choosing an engagement ring or gift to providing in-store or virtual appointments, we're always at your service.
Carved by hand
Details you find later
The kind you notice on the second look, then keep looking for.
- 01 Old European cutSoft, candlelit facets.
- 02 Milgrain bezelThe stone framed in a beaded rim.
- 03 Clean cathedralShoulders rise simply, made to stack.
Made to go with
What works with The Marlowe
Shapes, golds and bands we've already made for this setting.
Another shape in mind? Start a custom build- Signature shape Old European cut2 to 5 carats, bezel set low.
- Gold 14K yellow, white or rose · Platinum 950
Carved & Vintage
Made to look handed down
Engraving, milgrain and old cuts, made new at our bench.
Every order, not on request
You see your diamond before we set it
- 1 You chooseYour setting, carat and gold.
- 2 You see itA video of your exact diamond and its IGI report, within 24 hours.
- 3 We set itApprove it, and we set your ring by hand.
DEF color · VS2+ clarity · IGI certified
Postcards from our couples
Real rings, real people, shared with their permission.
