A lab grown diamond does not go cloudy simply because time has passed. GIA states that laboratory grown diamonds have essentially the same chemical composition, crystal structure and physical properties as natural diamonds. When a stone looks hazy, the cause is usually on the surface, in the setting, or already recorded as a clarity characteristic, rather than a change that appears with age.
Why the myth appears
People sometimes confuse lab grown diamonds with simulants. GIA is clear that lab grown diamonds are real diamonds, while materials such as cubic zirconia only look similar and have different chemical and physical properties. A simulant can scuff and lose its surface over years of wear in a way a diamond does not. That difference is about the material, not the age of a lab grown stone.
GIA also rates diamond as 10 on the Mohs hardness scale, and notes that only a diamond can scratch a diamond. Hardness is not the same as toughness. A hard blow can still chip any diamond, natural or lab grown, but a chip is damage you can point to, not a slow cloud that appears on its own.
Haze that was already in the stone
GIA defines a cloud as many tightly grouped pinpoints that might be too small to distinguish individually but together have a hazy appearance. Those pinpoints form as the crystal grows. They are graded on the report at the time the stone is examined, and they do not spread later through ordinary wear.
That is why the report matters before you approve a stone. If a lab grown diamond looks milky in every light, even when it is clean, the cause may already be on the certificate. We do not begin making a ring until you have approved the stone and the design in writing.
Haze from dirt, oil or extreme heat
The everyday cause of a dull diamond is far less dramatic. Soap, lotion and skin oil collect on the pavilion, the underside of the stone, and in the corners of the setting. Our guide to why a diamond looks cloudy walks through a gentle clean with warm water and mild washing up liquid.
GIA says diamonds can be cleaned safely with lint free cloths, commercial jewellery cleaning solutions and household detergents. It does not recommend powdered abrasive cleaners, or ultrasonic or steam cleaners, for home use, because those methods can loosen stones.
A rarer cause is extreme heat. GIA notes that diamonds will burn at about 850 degrees Celsius, a temperature that house fires and jewellers’ torches can reach, and that a house fire has left a diamond with a white, cloudy appearance. That is thermal damage, not a lab grown stone ageing, and the same risk applies to a natural diamond.
If you are comparing materials, see our note on whether lab grown diamonds look different, browse our lab grown colourless diamonds, or contact us with a report in front of you.
Frequently asked questions
Do lab grown diamonds go cloudy over time?
No. A lab grown diamond has essentially the same chemical composition, crystal structure and physical properties as a natural diamond, so it does not age into a haze in ordinary wear.
Why does my lab grown diamond look hazy now?
The usual cause is dirt or oil on the stone or in the setting, which a gentle clean can remove. If it stays dull, the haze may be a clarity characteristic that was already in the stone, or the setting may need a check.
What is a cloud on a diamond report?
GIA defines a cloud as many tightly grouped pinpoints that might be too small to distinguish individually but together have a hazy appearance. That feature is there from growth, not something that spreads later through wear.
Can heat make a diamond look cloudy?
GIA notes that diamonds can burn at about 850 degrees Celsius, and that a house fire has caused a white, cloudy appearance in a diamond. That is damage from extreme heat, not ordinary ageing, and it applies to natural and lab grown stones.