Today, most diamonds over half a carat are sold with a report from one of dozens of “independent” laboratories. These laboratories offer opinions of the quality grades of the diamond and possibly other information such as cut grade and light performance. It is important to note that not all laboratories are created equal. Some labs are known in the trade to be more “lenient” in their grading of the diamonds where others may be thought to be stricter. Consumers often wonder how this can be since diamond grading is considered a worldwide standard. Although it is true that a standard exists, the system is still subjective. After all, a grading report is a document of the lab’s opinion. Some labs rely on this subjectivity as a fallback position to allow them to be more lenient. Other factors that affect the quality of the lab are the number of graders that are required to look at each diamond (some labs may require only one while others may require a minimum of two), the experience of the lab, the quality control procedures, etc. Therefore, when comparing diamonds and diamond prices, the 4Cs are not the only factors to consider for a valid comparison. The laboratory should also be considered. This is not to say to accept one over another but to be aware of the differences that may exist.