Someone asked Leilei what size a 1 carat pear is. She wrote it out on a note and photographed it.
That note is the short answer we give a dozen times a month. Here it is typed out, because the numbers are the point.
| Marquise | Millimetres |
|---|---|
| 0.3 ct | 3 × 6 mm |
| 0.4 ct | 3.5 × 7 mm |
| 0.5 ct | 4 × 8 mm |
| 1 ct | 5 × 10 mm |
| 2 ct | 6.5 × 13 mm |
| 3 ct | 7 × 14 mm |
| Pear | Millimetres |
|---|---|
| 0.3 ct | 3 × 5 mm |
| 0.5 ct | 4 × 6 mm |
| 0.8 ct | 5 × 7 mm |
| 1 ct | 5 × 8 mm |
| 2 ct | 7 × 10 mm |
| 3 ct | 8 × 11 mm |
Then we went and checked it
Before publishing someone's handwriting we compared it with the size charts already out there. For marquise, everyone lands in the same place: 0.5 ct is 4 × 8, 1 ct is 5 × 10, 2 ct is 6.5 × 13. Three charts, three times the same answer.
For pear, they do not agree at all.
| What "1 carat pear" means | Millimetres | Size on the finger |
|---|---|---|
| Our note | 5 × 8 mm | 100% |
| A second published chart | 5.5 × 9 mm | 124% |
| A third published chart | 5.6–5.8 × 8.4–8.9 mm | 117–130% |
Same two words. Between a fifth and a third more stone on the finger. Order "one carat pear" from three suppliers and you can receive three visibly different stones, every one of them correctly described.
Why pear is the shape that does this
Carat is weight, not size. The same weight can be cut long and narrow or short and wide, and the thing that decides which is the length-to-width ratio — a number nobody quotes and everybody assumes.
Marquise has a convention: it is cut at about 2:1, near enough always. Fix the ratio and the millimetres follow from the weight, which is why the marquise charts agree.
Pear has no such convention. In normal use it runs from about 1.50 to 1.75, and every chart quietly picks one. A 1.50 pear is a plump, rounded drop; a 1.75 is a long tapered one. Both are 1 carat. Neither chart is wrong.
The part that costs money
None of this matters until something has already been made. Then it matters a great deal, because a seat is cut to millimetres, not to carats. A setting built for a 5 × 8 pear will not take a 5.5 × 9, and a 5 × 8 dropped into a seat cut for 5.5 × 9 sits loose.
So the carat name is fine for a conversation and useless for an order. Every stone on our site is listed by its millimetres for exactly that reason.
What to send us
Millimetres, from wherever you have them: the stone report on your CAD file, the seat you have already cut, a stone you are matching, or a caliper reading off the piece in front of you.
If all you have is "1 carat pear", say that — it is a perfectly normal place to start. We will tell you the millimetres we would cut, and you confirm them before anything is cut. Custom cutting runs in 0.5 mm steps; stock melee is calibrated finer, every 0.1 mm.
And if you cannot picture the difference
Then we lay the sizes out and photograph them, which is quicker than arguing about millimetres in a message.
Four oval sizes in a row on a hand, largest to smallest, with the millimetres written beside them. Real stones at real size. It takes us a few minutes and it ends the conversation.
Our sizes, by millimetre
Nothing is quoted; every size is priced on its page, and the minimum order is one stone.
- Pear melee — 2.5 × 1.5 mm to 5 × 3 mm
- Marquise melee — 3 × 1.5 mm to 7 × 3.5 mm
- Pear stones above melee size, by the carat
- Round melee size chart — mm, stones per carat
Bring us the job, not the carat
Send a photograph, a CAD file with its stone report, a grading report, a drawing, or one sentence about what you are making. If it is vague we will ask a question or two, then go and put the real stones on the counter and send you the pictures.
Message Leilei on WhatsApp — replies come the same day, and we work China time, GMT+8.
This note
| Asked | "What size is a 1 carat pear?" |
| Answered | Handwritten, photographed, sent back the same day |
| Shapes covered | Marquise and pear, 0.3 ct to 3 ct |
| Checked against | Three published size charts |
| Agreement | Marquise: all three match. Pear: up to about 30% apart in size |
| Custom cut steps | 0.5 mm — stock melee is finer, every 0.1 mm |
| Tolerance | ±0.1 mm, in writing |
How ordering by design works → · Free stone count calculator → · ±0.1 mm calibration guarantee →
Frequently asked questions
What size is a 1 carat pear in mm?
We cut a 1 carat pear at 5 x 8 mm, but published charts disagree: others give 5.5 x 9 mm or 5.6-5.8 x 8.4-8.9 mm for the same carat name. That is between a fifth and a third more stone on the finger for the same two words. Carat is weight, not size, so order the millimetres rather than the carat name.
What size is a 1 carat marquise in mm?
5 x 10 mm. Marquise is conventionally cut at about a 2:1 length-to-width ratio, so the published charts agree closely on this one: 0.5 ct is 4 x 8 mm, 1 ct is 5 x 10 mm, 2 ct is 6.5 x 13 mm and 3 ct is about 7 x 14 mm.
Why do size charts give different mm for the same carat weight?
Because carat is weight and the length-to-width ratio is a free variable. The same weight can be cut long and narrow or short and wide. Marquise has a settled convention near 2:1, so charts agree. Pear runs anywhere from about 1.50 to 1.75 and each chart picks one, which is why a 1 carat pear is quoted anywhere from 5 x 8 mm to 5.5 x 9 mm.
Should I order moissanite by carat or by millimetre?
By millimetre. A setting seat is cut to millimetres, so a seat made for a 5 x 8 mm pear will not take a 5.5 x 9 mm stone, and a 5 x 8 mm stone sits loose in a seat cut for 5.5 x 9 mm. Carat names are fine for a conversation and unreliable for an order.
Can you cut a pear or marquise to a size that is not listed?
Yes. Custom cutting runs in 0.5 mm steps and takes about seven days for a single stone. Send the millimetres you need, or tell us the carat name you are working to and we will confirm the millimetres we would cut before anything goes into cutting. Stock melee is calibrated finer, every 0.1 mm.