UGL Labs Checking diamonds

Review of UGL Labs

Quite curiously, for an industry worth so much, diamond buying and selling don’t have too many regulations.

Kimberley Process and conflict diamonds aside, there are actually very few rules on who can buy or sell diamonds. Nor are there any rules on the quality of the diamonds on offer. There are consumer laws that say how a diamond must be described in certain circumstances, but little else.

However, if a dealer is serious about doing things properly, all their diamonds will be certified. Any number of recognized organizations can issue certificates. Without a grading certificate, it is complicated to sell a diamond through regular channels. At the very least, the lack of a certificate will considerably reduce the diamond’s value. The certificate gives the buyer all the information they need to have the stone valued independently. It also gives specific information on the size and anatomy of the diamond.

Most crucially, it gives information on the 4Cs. Each C of color, clarity, cut, and carat weight is subject to evaluation and grading. These, collectively, will then lead towards a value based on the current market.

Who is UGL Labs?

UGL Labs Checking diamonds with scope

Universal Gemological Laboratory is a separate business that finds gemstones and jewelry and gives them ratings. People and businesses in the gold business hire us to do these things. Here are some of the things they offer:

  • Pre-purchase evaluation
  • Post-purchase confirmation
  • Appraisal to obtain insurance
  • Diamond certification
  • Appraisal for liquidation
  • Appraisal for tax purposes
  • Colored stone identification
  • Diamond mapping of inclusions

Who works in UGL Labs?

UGL Worker Diamond tester

These are just a few of the many things we do. Everyone on our team is a graduate gemologist or diamond graduate (G.I.A.).

People will treat you with the attention you deserve when you go to the Universal Gemological Laboratory. We go into great depth about the whole appraisal process. There is no time when you are not there; the evaluation is done right before you.

The people who work at Universal Gemological Laboratory all have at least one of the following credentials:

  • Graduate Gemologist (G.I.A.)
  • Associate Member, ISA
  • Senior Accredited Gemologist, AGA
  • Diamond Graduate (G.I.A.)

Who uses UGL?

UGL Labs Girl with diamond earing

A wide variety of clients uses UGL’s services:

  • Banks
  • Diamond wholesalers
  • Online sellers
  • Retail-buying public
  • Retail stores
  • TV jewelry sellers

UGL Labs Services

UGL Labs Services diamond getting checked
  • INDEPENDENT JEWELRY APPRAISALS – Anyone can get an expert appraisal from UGL USA, including people in the trade. It is done in front of you while you watch when we do an appraisal for the buyer. These people have been trained by the Gemological Institute of America and are happy to answer any questions you may have. All of the big insurance companies will accept our estimates.
  • PRE-PURCHASE & POST-PURCHASE EVALUATION SERVICES – If you want to make sure that what you are going to buy is what the seller says it is, or if you already bought something and want to make sure that it is what the seller said it was, bring it to UGL. As GIA Graduate Gemologists, we can tell you everything you need to know to know if you bought the right thing or are about to buy it.
  • COMPREHENSIVE SERVICE – UGL USA has many special reports for diamonds, colored stones, and jewelry, including a credit card-sized report called a “mini-appraisal.” It would look great in a stand with the mini-appraisal. We are a full-service lab, so we can give you grading, identification, and appraisal results for a lot of different reasons.
  • LASER INSCRIPTION – They offer laser engraving on gems through a third party that is insured and has a lot of experience. This will usually make the turn-around time 24 hours longer. They can put certificate numbers, logos, custom messages, and other things on them.
  • ONLINE RESULTVerify grading results using the certificate number online.

Diamond Basics

3 Shining diamonds

In history and myth, diamonds have been known as a girl’s best friend. A lot of people have given up their rights and kingdoms in exchange for diamonds. People in ancient Greece thought that the fire in a diamond represented the flame of love that never goes out. —Diamonds became easier to find and get in 1870 when huge mines were found in South Africa. Not only royalty could now buy gems, but anyone who liked them could do so.

The Birth of Diamond

miner holding diamond

Carbon that was hidden deep in the earth’s crust millions of years ago is where this rare and valuable mineral got its start. Diamond was made when carbon crystallized under a lot of heat and pressure. The diamond-filled rock was then pushed to the surface of the earth by volcanoes, where it was mined as diamond ore.

To find one rough diamond big enough and fine enough to cut into a one-carat gem, about 250 tons of ore must be dug, crushed, sorted, and sorted again. The diamonds are then put into over 2,000 different groups based on their size, shape, and quality. The great stones are then sent to big cutting centers to be looked at and marked so they can be cut. Lastly, they are cut, cleaned, and put in order with great care.

Four C’s

Four Diamonds

Most finished, polished diamonds will look pretty much the same to someone who hasn’t seen them before. But in reality, no two diamonds are the same; they are all unique, like stars. There are four things that all diamonds have in common: their cut, color, clarity, and carat weight. Each one is unique.


A jeweler’s “cut” refers to both the shape and size of the stone. Most of the time, people choose Round, Marquise, Pear, Emerald, Oval, Heart, Princess, or Radiant.

A princess or radiant diamond is the only type that doesn’t have 58 faces. A diamond cutter has to look at a rough stone and decide what shape the finished diamond will be. This is done by looking at the rough stone’s shape, where its flaws are located, its size, and how much weight will be lost during the cutting process.

If a diamond is cut and sized correctly, it will shine brightly because it will bend the light inside it and bounce it back up to the eye. The diamond may lose its “life” and sparkle if it is cut too deeply or too shallowly. Light may also leak out of the bottom of the diamond. You can’t get as much for these diamonds.

The cut is the most important of the 4 C’s. Why buy a gem that doesn’t sparkle, after all? How bright it is will depend on its size, shine, and clarity.


Color is a big part of how much a diamond is worth. As seen against a white background and under white lights, an alphabetical color scale is used to measure how much body color can be seen through the face of the diamond. Between “D” and “Z” are the letter grades.

  • Graded as D, E, and F for colorlessness. If you want the best diamond, these are the “colors” there are.
  • Ratings: G, H, I, and J for being almost colorless”. “Face-up,” these stones are colorless, with only faint traces of color noticeable to a skilled eye.
  • You can get a K, L, or M for faint yellow. Smaller versions of these stones are almost transparent when they are “face-up.” Some stones, especially bigger ones, will look colored.
  • If you look closely at these stones, ranked M through Z, you might notice that they have a yellow tint.


  • Flawless: Under 10x magnification, it has no flaws or inclusions.
  • Internally flawless: the same as above, with a few small flaws on the outside
  • Minute inclusions are hard for a trained viewer to see even at 10x magnification in VVS1 and VVS2.
  • VS1 and VS2: They have small features that are between being hard to find and being only slightly hard to find at 10x.
  • SI1 & SI2: Has significant inclusions that can be seen at 10x magnification
  • The entries in I-1, I-2, and I-3 range from being hard to see to being easy to see without any help.

Carat Weight

A carat is a unit of weight, not size. With a weight of only 0.5 grams, it is a very small unit of measurement. The word comes from the seed “carob,” which has a weight that is so steady that it was used as a measure for diamonds. There are 100 “points” in a carat. So, a diamond with 75 points is also known as a three-quarter-carat diamond.

UGL Certificates

UGL Certificates with diamond ring

One of the leading firms for diamond certification is Universal Gemological Laboratory or UGL.

UGL has been in operation since 1995, offering many different services.  For certification, each diamond undergoes intense scrutiny. Although opinion still plays a part, each of the 4Cs has well-set guidelines. Most of these are measurable using the correct tools, thereby taking out some of the subjectivity. Some aspects, such as color, will still depend on the eye of the expert, but the certificate will be otherwise mostly objective.

UGL certificates are very well regarded in the industry. There were concerns in the very early days that they were being overly generous in their evaluations. However, today, all their staff are highly qualified, with many trained by the Gemological Institute of America. GIA is the world’s leading issuer of diamond certificates and was instrumental in setting many of the standards currently in place. Because of the quality of training from GIA, UGL staff are all acknowledged experts.

After the undisputed leader GIA, UGL is generally one of the companies next in line in terms of certification quality. The certificates are thorough and accurate to the highest standards. If you are offered any item with a UGL certificate, you can assume it is a worthy indication of the item’s quality.

UGL Appraisals

Appraisals are very different from Certificates. It is jewelry pieces that have appraisals, rather than individual diamonds.

A UGL appraisal will contain all the relevant information for any piece of jewelry. It will contain a picture of the actual piece in question, for identification purposes in the future. It will also have information about each stone set in the piece, with color, cut, clarity, and carat weight. There are certain caveats to this, however.

Because the stones are already set, size and weight are approximations. Rarely will the stones be available for separate evaluation, so some assumptions are necessary. These assumptions are according to a precise set of calculations according to the parts of the stone that are visible. Symmetry is part of the original diamond grading, and so several measurements to establish the overall symmetry then allow an accurate weight measurement.

As well as the technical details of the piece, it will always be noted that the appraisal is subject to the mounting. The appraisal will also usually give the reason for the appraisal itself. This can be insurance, tax, valuation, or a number of other things.

Unless for a solitaire ring, diamonds separate from the center stone will be shown separately. They will not be all subject to individual appraisal, but rather as a combined weight and an estimate of the collective color. A brief summary of the piece often makes up part of the appraisal but is usually for the diamonds only.

Finally, the document will show the estimated retail value at the appraisal time. This is usually good enough for insurance companies for at least 12 months.

UGL appraisals do appear to be pretty accurate as far as valuations go. The information they contain is also comprehensive and very clear.

Overall Document Standard

As we’ve said, UGL is number two in the certification and appraisal stakes, behind GIA. This doesn’t mean UGL is any less relevant or accurate than GIA, although GIA certificates do still carry a premium and tend to increase the value of the diamond in question.

Still, UGL is an excellent way to establish the quality and value of a diamond. They are also vital if you intend to insure your ring or another piece of jewelry (which you should!). We all know that insurance companies are no fools when it comes to paying out money. That they readily accept UGL certificates and are valid and accurate both on quality and estimated cost should be an indication that the documents are well worth the effort and relatively low cost of acquiring.

We can’t speak to problems in the early years of UGL. All we can say is that if problems did exist with optimistic valuations, those problems appear to have been resolved. Nowadays, it’s easy for anybody to get more than one evaluation if they have any doubts. UGL wouldn’t have lasted over 20 years if they were in any way unreliable.

They will never be the equivalent of GIA in some people’s eyes, but that’s an issue for those people to deal with. For diamond certification and jewelry appraisal, UGL is a very good option.

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Their appraisal and evaluation is very good.

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