Update：With the popularity of lab grown diamonds, the word phosphorescence has come into our sight. If you want to learn about phosphorescence, please read the following.
Are you planning to buy a diamond recently? When you check a diamond’s GIA grading report, have you noticed the item called Fluorescence? Do you know that some diamonds will show special visual effects under ultraviolet light? Then, do all diamonds have fluorescence? How many grades does diamond fluorescence have? Also, how does the strength of fluorescence affect diamond prices? Many people wear fluorescent diamonds every day, so will it bring bad effects to human health? For most diamond buyers, fluorescence is not a key factor compared with the famous 4Cs. Here we sort out common questions about diamond fluorescence, you can keep reading to know more details.
Most natural diamonds in the world have fluorescence. Diamonds are formed naturally, so almost every single one contains inclusions of different kinds. These tiny flaws make the Mohs hardness of diamonds fail to reach the full score of 10. In the gemstone industry, 10 stands for the hardest level. Gem experts have found that the degree of fluorescence is closely related to diamond hardness. The stronger the fluorescence is, the softer the diamond will be. It also means the diamond has lower compression resistance. In short, diamonds with strong fluorescence are easier to get damaged than non-fluorescent ones. Diamond hardness and fluorescence are in inverse proportion.
For high color grade diamonds, from color D to G, strong fluorescence will make the stone look hazy and foggy. But fluorescence is not totally a bad thing. It can improve the appearance of low color grade diamonds. Fluorescent diamonds usually have better and bigger fire than those without fluorescence. If you just buy diamonds for daily wear instead of investment, you can pick diamonds with faint or medium fluorescence, they perform great on fire display. The slight yellow tone inside diamonds can be neutralized by blue fluorescence, so the visual color of the diamond will look one grade higher. For example, a J-color diamond with blue fluorescence looks like an I-color diamond, and appears much whiter. However, diamonds with strong yellow fluorescence will look dull all the time. We do not suggest you buy this kind of diamond at all.
Blue Nile diamonds are worth buying：1，Both milky tint and brown hue:Tap to see full diamond info 2，The diamond has milkiness:Click to view detailed diamond information 3，The diamond has medium green fluorescence.:View details 4，The diamond has a cavity:See details
The value of a diamond is not only decided by color, clarity, carat weight and cut. Non-fluorescent diamonds are regarded purer in the market, so their prices are higher. Here is the current price difference between fluorescent diamonds and non-fluorescent ones. Diamonds with faint fluorescence are about 3% cheaper. Medium fluorescence ones have a 10% price gap. For strong fluorescence diamonds, the price difference can reach 20%. Please note that diamond price is affected by many factors, so these numbers are just for reference. Normally, fluorescence has a bigger impact on diamonds with high color, clarity and carat grades. As for small diamonds below 20 points, or diamonds with color grade lower than M, fluorescence barely changes their value.
When it comes to high color diamonds, fluorescence mainly influences their sparkle, and this change is quite obvious under a 10x magnifying glass, bringing a misty look. Of course, everyone has different tastes. Some customers actually love this special look of fluorescent diamonds.
Fluorescence is a natural property of diamonds. It refers to the visible blue or yellow light released when diamonds are exposed to strong ultraviolet rays. The most common colors are pale blue-white and light yellow. Diamond fluorescence has different intensity levels. GIA sets its standard as None, Faint, Medium Blue, Medium Yellow, Strong Blue and Strong Yellow. IGI uses another set of grades: None, Very Slight, Slight and Strong.
Most diamonds have fluorescence. Under normal natural light, you can hardly tell the difference caused by fluorescence on diamond outlook. The basic principle of fluorescence is simple. There are nitrogen impurities inside diamonds. After absorbing energy from ultraviolet light, these elements will release energy again at a lower energy level and produce visible light. There is no radiation produced during this process. Wearing fluorescent diamonds will not cause any harm to human body or health.
