A natural phenomenon
Approximately one in three diamonds will glow under ultraviolet light, a natural phenomenon known as fluorescence. The vast majority of these stones have blue fluorescence of varying strength, though a very small percentage fluoresce in other colours, including green, yellow and red. In most cases, fluorescence is caused by the presence of nitrogen as a trace element impurity in diamond.
Some diamonds with "very strong" fluorescence can have a "milky" or "oily" look to them. These rare stones are known as "overblues." A study by the GIA found that with the exception of "overblues" and yellow fluorescent diamonds, fluorescence has little effect on transparency.
Generally it isn’t advisable to buy strongly fluorescent diamonds, but in certain instances it might be a good idea - for example, if your budget limits you to a diamond with a slight yellowish tint. In this case, some blue fluorescence might actually cancel out the yellow and make the diamond appear whiter than it actually is.
You can learn more about how diamonds are graded at our diamond grading page.
Ethically Sourced, Exquisite Design
Browse our ready-to-buy collections
Call us on 020 7499 2012 or come and see us in person at our showroom close to Bond Street station, London. You’ll be able to discover our stunning collection, speak to our experts one-on-one and explore the option of creating your very own bespoke ring. We aim to respond to appointment booking emails within 1 hour.
"Ingle & Rhode is one of London's number one jewellery destinations"
"Ingle & Rhode... the jewellers leading the way to cleaner, greener gold."
"Better shut the cabinet doors, I'm feeling involuntary kleptomania coming on"
"Ingle & Rhode is perfect for couples who want style and luxury with a conscience"
"Ingle & Rhode... committed to ethical sourcing."
"Ingle & Rhode produces beautiful pieces that you can wear with a clear conscience."