How would you feel if your favorite soft drink tasted different in every can you drank? You expect a coke to taste like coke everywhere. In business, this is called a commodity. The soda is the same and you can shop based on price or convenience; the product is the same. People like shopping this way. I like it this way. Diamonds are not this way.
The four C’s of diamonds are not that old, less then 100 years. Before that system every business and diamond seller had their own system. It was impossible to buy a diamond without seeing it first. The GIA four C system is supposed to be an agreed upon grading standard but in reality this is not always the case. Today, to make the grading standard more uniform, diamond certification by grading laboratories is thought to make diamonds a commodity. Again the dream is not the reality.
The nature of diamonds is that every diamond is unique. Diamond reports don’t tell the whole story.
First, it is well known that not all diamond grading labs grade with the same standard. GIA and AGS use the most technical standards. EGL uses a looser grading standard, I call market grading. In addition, EGL has a franchise like business model and different EGL labs grade wildly different. Some other labs like IGI and many more will put on a report what the customer, the diamond owner wants the report to say. So the first problem you have to contend with is what lab graded the diamond and how they grade.
Next, understanding a diamond report is not just seeing the four C’s grade to compare diamonds. The same lab can grade two stones H VS2 1.00 carat and the value of the two diamonds can be hundreds, if not thousands of dollars different. It is a favorite trick of some diamond wholesalers to use GIA labs for very poorly cut diamonds. The general public knows GIA is a quality lab and mistakenly thinks the diamond is quality.
The Dirty Little Secret of Diamond Grading
So, two 1.00 carat H VS2 accurately graded diamonds from GIA labs can be worth thousands of dollars apart. How? One way is the cut of the diamond. Diamond one can be a nice cut (61.5%) and diamond two could be a very poor cut (68%). Another way is both can have a 61.5% depth but diamond one has the correct crown to pavilion proportion and diamond two has a very deep pavilion and extremely thin crown. Other ways are how thick the girdle is and how it is made. If the diamond has fluorescence is an issue. And if the fluorescence has a negative impact on the diamond is another question. The nature and position of the inclusions can have a big impact on diamond value as well. All these issues impacting value are on diamonds with an accurate grading report. Does this sound like a commodity?
The nature of diamonds is that every diamond is unique. Diamond reports don’t tell the whole story. It takes some training and experience to accurately assess the value of a diamond and gemological equipment to check the grades. I see internet diamond buyers all the time not getting what they think they are getting. The surest way to get ripped off when buying a diamond is to think of it as a commodity. Hopefully you know you can trust us at Arden Jewelers to use our experience and equipment to find the best diamond value for you or your friends. If you have any questions please feel free to ask at any time.