Diamond myths and facts
Common beliefs, and what’s actually true.
A lot of what people hear about diamonds is out of date or only half right. These are the beliefs we hear most in the showroom, and the facts behind them.
From the CTJ Jewellery team, led by founder Greg Ward
- Myth
Lab-grown diamonds are fake diamonds.
FactLab-grown diamonds are real diamonds, with the same chemical, physical and optical properties as natural diamonds. Only their origin differs.
- Myth
A grading report tells you everything.
FactA report records grades, not beauty. Two diamonds with identical reports can look very different in real life.
- Myth
Higher grades always look better.
FactAbove eye-clean clarity and near-colourless colour, most differences can’t be seen without magnification.
- Myth
Bigger carat means a bigger-looking diamond.
FactCarat is weight. Cut and shape change how large a diamond looks face-up.
- Myth
Diamonds are an investment.
FactWe don’t describe diamonds as investments. Jewellery is made to be worn, enjoyed and passed on.
- Myth
You can tell natural from lab-grown by eye.
FactYou can’t. It takes specialist laboratory equipment, which is why reports state the origin.
More myths we hear
- Myth
Diamonds are indestructible.
FactDiamond is the hardest natural material, but a hard knock at the right angle can chip it. Settings wear too, so inspect jewellery at least once every 12 months.
- Myth
A bigger diamond always costs more.
FactCut, colour, clarity and origin all move price. A smaller, better-graded natural diamond can cost more than a larger lab-grown one.
- Myth
Fluorescence always ruins a diamond.
FactMost fluorescence has no visible effect. Very strong fluorescence can make some diamonds look hazy, so judge each one by eye.
- Myth
All white gold looks the same.
FactWhite gold is rhodium plated. When the plating wears, the warmer alloy shows, which is why replating exists.