Quality and prices per carat
Certificated Diamonds a Question of Quality...   There are various certification and grading organisations throughout the world. Each laboratory provides reports on diamonds. Most of the laboratories are accredited to ISO 17025, which is an international standard for laboratories. Listed below are just some of them. SHERRY JEWELLERY supplies diamonds from these institutes.
International grading laboratories		HRD Princess cut F colour vs 2

HRD			(Hoge Raad voor Diamant)   based in Antwerp Belgium
IGI			(International Gemmological Institute) Is the world’s largest independent laboratory  for grading and evaluation of diamonds and coloured gemstones
GIA			(Gemmological Institute of America) based in California with laboratories worldwide including India, South Africa, Thailand.
EGL			(European Gemmological Laboratory) based in Antwerp with laboratories worldwide
Anchor Cert			The First UK based laboratory accredited to ISO 17025 (see above)  AnchorCert  is part of the Birmingham Assay Office. Based in Birmingham, United Kingdom

Certified diamonds
Diamond certificates, record all the relevant information pertaining to the diamond, including carat weight, colour grade, clarity grade, measurements and physical properties, as well as plotting diagrams. Many laboratories will also supply the diamond in a sealed plastic package, along with the certificates. Though this is not  necessary if you’re buying from a reputable source and can sometimes impair a really clear view of the gem.
Non-certificated diamonds
SHERRY JEWELLERY also supplies diamonds that do not carry certificates. This does not imply that the un-certificated stones are of an inferior quality. Diamonds that are not certificated, tend to be less expensive, as there has not been a charge levied, to have the gem independently graded. However, each diamond that we sell, has been assessed using the same criteria as the Grading Laboratories. We can also have any un-certificated gem, certificated, if desired.   It is very important to also note, that a good report of the 4 Cs, doesn’t necessarily mean that the quality of the crystal is good. There are many different qualities of diamond crystal, from cloudy through to clear and this will not be specified on a certificate.   SHERRY JEWELLERY can source all grades of diamonds and can show a selection based  on your preferences and budget.
Prices per carat
Prices of diamonds vary considerably. The price is entirely dependent on the quality of each stone. Current diamond prices ( Dec 09 )  for a 1 carat, brilliant cut diamond, range from about £3,350 to £15,000. This would be for stones starting at about J colour I clarity, right through to a D IF gem. Each grade characteristic of the diamond will contribute to the price of the stone. So you may see a stone with fantastic colour, but visible inclusions, or a very clean gem, which is off-white in colour. It’s up to the buyer, to decide what the important factors are for themselves, when choosing. Where possible, we’d always recommend that you buy the diamond un-set (loose), as flaws can sometimes be concealed under the setting.