What is diamond fluorescence?
Diamonds that are said to be fluorescent contain particles that emit a visible (usually blue) glow when exposed to UV lighting. In rare cases, high levels of fluorescence can make stones appear milky or hazy, although for the most part fluorescence does not generally impact beauty or sparkle and can even make some lower colours (I, J, K, L, etc.) appear more colourless or white. Nonetheless, fluorescent diamonds are usually cheaper and provided the effect is not readily visible may offer good value for money.
HOW DOES FLUORESCENCE IMPACT DIAMOND PRICING?
Historically, strongly fluorescent diamonds have been marked down in price next to their non-fluorescent counterparts. Typically, higher colour (D-H) non-fluorescent diamonds will sell for 10-30% more than similar stones that exhibited very strong blue fluorescence. However, lower colour (I–N) diamonds with very strong fluorescence were priced up to 5% higher than similar non-fluorescing stones. This is likely due to the perception that blue fluorescence can mask the undesirable yellow tones found in some stones.