Are sapphires graded like diamonds, using a grading scale like the 4Cs? How do I know the sapphire I am buying is worth the asking price? Why is one sapphire so much more expensive than another of the same size and carat weight?
These are some of the common questions that we receive about our sapphire jewelry. In this article, we will guide you through the characteristics that definea sapphire’s value.
Is there a Standardized Grading System for Sapphire?
Unlike diamonds, that are graded on a scale based on the 4Cs (Cut, Color, Clarity and Carat Weight), there isn’t a standardized grading scale or system for understanding the value of sapphires throughout the industry.
Though there is not a specific scale, gemologists still look at the same quality characteristics in colored gemstones as we do in diamonds. Color, cut, clarity, and carat weight are all considered when we determine the value of the gemstone. We also like to add a fifth “C” for colored stones: country of origin. Through the rest of the article, we will describe the 5Cs as they relate to sapphire and other colored gemstones.
Sapphire Color: Body-Color and Saturation
Arguably the most important quality characteristic of a sapphire is its color. There are two components to sapphire color, the gemstone’s main body color and the gemstone’s saturation of color.
Sapphire is one of the most unique gemstones, because it forms in every color of the rainbow. At Market Square, we have pinks, purples, blues, greens, oranges, and yellows mounted for sale. When a sapphire forms with the main bodycolor as red, it is called a ruby. Most people think of sapphire as a blue gemstone. This blue color is also the most valuable.
There are other gemstones that have a similar body color as a sapphire. Take a look at he gemstone kyanite, for a less expensive alternative. Or spinel, for a smokey midnight blue color comparison. Neither, though, have the incredible brilliance and sparkle that a sapphire does!
In general, as a sapphire deepens in color, it gains value. But, it only increases in value until a certain point, whereupon it becomes too dark and loses value dramatically. When it become blue/black and inky in color, it is much less expensive than a medium/dark stone.
The highest valued sapphire is what gemologists call “cornflower blue”. This distinction is reserved for gemstones that have the finest medium blue color that is often described as velvety. Sapphires that have this color distinction are often stones coming from the northern region of India, Kashmir.
Sapphire Cut: All Ovals Are Not Created Equal
There are a few considerations when looking at the cut of the gemstone: precision, proportion, style of faceting, and overall sparkle.
The cut is what makes beautiful gem material transform into an exquisite gemstone that sparkles with life. Precisely cut gemstones are evenly colored from top to bottom and side to side. A well-cut gemstone’s culet is centered, its facets are precise and symmetrical, its shape is pleasant and uniform, and when you look inside the stone it is not windowed or shadowed.
In regards to proportions, the perfectly cut gemstone has no extraneous carat weight. It is cut for optimal light refraction. That being said, sapphires, especially Ceylon stones, tend to be cut deeply in order to increase their saturation of color. The deeper the gemstone, the more dense the color and the more valuable the gemstone becomes. Cutters have to weigh the advantages of cutter material precisely and cutting material so that the color is deep and rich.
Sapphires are not cut to strict mathematical proportions like diamonds are. On the contrary, sapphires are often cut to retain carat weight and maximize brilliance and minimize visible inclusions, so sometimes they can be a bit asymmetrical/imperfect unlike diamonds.
Sapphire Clarity: Common Inclusions and Color Banding
Most sapphires have natural inclusions. It’s almost impossible to find a sapphire without them due to the way sapphire crystals form in nature. The value of the gemstone is determined based on the type of inclusion and more importantly how it impacts the stone’s overall visual appearance.
Sapphires have a number of types of inclusions, such as small crystals, needle-like rutile inclusions that form in parallel lines throughout the gemstone, and what is called a fingerprint inclusion, which looks like a far away galaxy of stars or a human fingerprint. Stones from Kashmir, which are considered the finest sapphire in the world, usually have an array of needle like inclusions. These needles are the characteristic that gives the stones their distinctive velvety appearance.
Most inclusions are only visible under 10x magnification, under a microscope, or when you shine a bright light through the gemstone. Inclusions that you can see with your naked eye do impact the value of the sapphire dramatically.
Inclusions can tell us so much about a gemstone. Sometimes they can point to a particular country of origin, or region, or even a specific mine. They can also tell us whether the gemstone has been heat treated. To learn more about the sapphire heat treatment process, please click here.
Sapphire Carat Weight: Is Larger Always Better?
The larger the gemstone the more valuable and rare the item is. There are certain thresholds that a sapphire needs to reach to jump-up in value. For instance, when a sapphire is over 1 carat, it increases the price per carat. When a sapphire is over 3 carats, it increases dramatically as well. This is standard with all colored gemstones and diamonds.
Sapphire Country of Origin: Kashmir, Sri Lankan, Thai, African
We have a whole other blog post that talks about country of origin for sapphire. Many of our gemstones come from Sri Lanka and are called Ceylon stones. To access this post to read more about our 5th C, click here.
Have a question about one of our items or need assistance understanding how a stone fits within these quality characteristics? Contact Alex, our online sales manager, for further information.