Cut
How well the diamond is proportioned and polished. Its sparkle and brilliance depend on its cut more than anything else. GIA grades the cut of round brilliants:
- Excellent
- Very Good
- Good
- Fair
- Poor
Every diamond we set is GIA certified
The Gemological Institute of America is the independent, not-for-profit authority that created the 4Cs and grades diamonds to the same standard worldwide. Every diamond we place in your jewellery comes with its GIA report and carries GIA's laser inscription, so you know exactly what you're buying.
About GIA
Founded in 1931, GIA is the world's foremost authority on diamonds, coloured stones and pearls: a public-benefit, not-for-profit institute and the leading source of knowledge, standards and education in gems and jewellery.
Education
Students around the world learn gemmology at GIA, from the basics to the qualifications the trade relies on.
Research
GIA's research into how gems form, and how they're treated or made in a lab, keeps grading honest.
Protection
Unbiased grading and global standards protect anyone buying a diamond, wherever they buy it.
The 4Cs
In the 1940s GIA created the 4Cs and the International Diamond Grading System, the language every jeweller uses to describe a diamond. Here's what each grade means.
Colour
Graded from D (colourless) to Z (light yellow or brown). The closer to colourless, the rarer the diamond and the higher its value.
- D E FColourless
- G H I JNear colourless
- K L MFaint
- N to RVery light
- S to ZLight
Clarity
How free the diamond is from tiny inclusions and blemishes, judged under 10× magnification. The fewer there are, the rarer the diamond.
- FLFlawless
- IFInternally flawless
- VVS1 VVS2Very, very slightly included
- VS1 VS2Very slightly included
- SI1 SI2Slightly included
- I1 I2 I3Included
Carat
The diamond's weight. One carat is 0.2 grams, about the weight of a paperclip. Typical width of a round brilliant, enlarged and to scale with each other:
- 0.25ct4.1mm
- 0.50ct5.2mm
- 0.75ct5.8mm
- 1.00ct6.5mm
- 1.50ct7.4mm
- 2.00ct8.2mm
What your GIA report shows
Your diamond's report is its independent record. The report number is also laser-inscribed on the diamond itself, so the stone and the paperwork can always be matched.
You can check any report on GIA's own website: GIA Report Check (opens in a new tab).
Diamond grading report- Report number
- Unique to your diamond, and laser-inscribed on its edge (the girdle).
- Shape and cutting style
- For example, round brilliant or princess cut.
- Measurements
- The diamond’s dimensions in millimetres.
- The 4Cs
- Carat weight, colour grade, clarity grade and, for round brilliants, cut grade.
- Polish and symmetry
- How finely the facets are finished and lined up.
- Fluorescence
- Whether the diamond glows under ultraviolet light, and how strongly.
- Proportions and clarity plot
- A diagram of the cut, and a map of any inclusions.
How we use GIA
We use GIA's grading to make sure every diamond we set is the best it can be for your budget. Because the grades are independent of us, you can compare like with like, and know exactly what you're paying for.
When you choose a diamond, we'll sit down with you, show you diamonds side by side and go through each report with you, so you can decide which of the 4Cs matter most to you.
Every diamond carries GIA's laser inscription and comes with its documentation, confirming that it's authentic.
Diamond shapes
The shape is the outline of the diamond from above. Choose one to see our engagement rings in that shape.
Our customers
4.4 out of 5 on Googlefrom 91 reviews
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A selection of recent five-star reviews
First time caller into the shop yesterday as I couldn’t remove my ring, the staff were lovely and Paul managed to remove my ring without causing any damage to it.Lovely shop very welcoming thankyou 🌟🌟🌟🌟🌟
Sue W.Rated 5 out of 5, Google review, February 2026 5 star service from Paul Granelli jewellers. Paul and his staff were very professional, helpful and friendly. I contacted Paul to assess my damaged engagement ring and he did an amazing job of repairing it.My engagement ring looks brand new now. Thank you so much absolutely delighted. Can definitely recommend.
C M.Rated 5 out of 5, Google review, September 2025 I got my ring back today after some work it needed doing and it looks like a brand new ring ! So chuffed , beautiful craftsmanship.I will be back with some items that need a much needed polish , thank you and Merry Christmas !
Lois B.Rated 5 out of 5, Google review, December 2024 I’ve used this jewellers for a few years to have my wife’s rings cleaned and re coated and can’t fault the care and service provided .The staff are extremely helpful and paul helped me out recently when buying a pre owned watch which he didn’t really have to do but he goes above and beyond for his customers.Highly recommend jewellers
Macca 2019Rated 5 out of 5, Google review, June 2024 Great service and quality work. I had a simple ring size adjustment, but I can imagine the service would be every bit as good with complicated intricate pieces.
Stewart W.Rated 5 out of 5, Google review, March 2024 I went into Paul’s to have my rings resized. He’s done a fantastic job as always - they’ve also been polished and look brand new again. Always a very friendly, personal service when we visit. Thanks again
Holly G.Rated 5 out of 5, Google review, September 2023 Amazing service from Paul and his team we got wedding rings and engagement ring and the guys were first class, I wouldn’t go anywhere else .
Jon B.Rated 5 out of 5, Google review, March 2023 Reset my engagement ring and I’m really happy with the end result
Gill C.Rated 5 out of 5, Google review, November 2022
See the difference in person
Diamonds are best compared side by side. Book a free appointment and we'll show you how cut, colour and clarity change what you see.
Paul Granelli Jewellers
4 Bramhall Lane South, Bramhall, Stockport SK7 1AF
Open 10am–5pm. Closed Wednesdays and Sundays.