Loose Stones: How to Buy a Loose Moissanite or Lab Diamond

Buying loose is the most flexible way to buy a stone, and usually the cheapest. Here is how to do it properly.

Millimetres vs carats

Stones are sold by carat weight but set by millimetre size. That mismatch is why a 6.5mm round is sold as '1ct equivalent' — it has the spread of a 1ct diamond but weighs less. Always buy by millimetre when you already have a setting.

What to check before ordering

• The exact measurement in millimetres
• Cut and clarity grade, and the certificate
• Colour grade (D–F is colourless)
• Whether the stone is calibrated to standard setting sizes

Comparing moissanite and lab-grown diamond

Moissanite gives more fire and a lower price. Lab-grown diamond gives more white brilliance and an IGI report. Order one of each if you are undecided — loose stones are cheap enough to compare side by side.

Bulk and wholesale

We supply jewellers and brands with consistent, repeatable stones and can match pairs for earrings. Ask for a wholesale quote with your sizes and quantities.