The colour scale for diamonds ranges from D (absolutely colourless) to Z (distinctly yellowish or brownish). For lab-grown diamonds, this exact GIA scale is used, since they are chemically identical to natural diamonds.

With moissanite, the situation is a bit different. Earlier generations often had a slight yellow or green tint—which was one of the main arguments against the stone. However, modern premium moissanites, such as those we use at Velur, easily achieve grades D, E, and F. They are completely colourless.

One detail that is often overlooked: The larger the stone, the easier it is for the eye to perceive subtle colour nuances. With stones larger than 2 carats (DEW), even a minimal difference in colour tends to be more noticeable. For this reason, we almost always recommend grades D or E to our customers when it comes to larger stones. It’s simply the safest bet.

Clarity describes the presence of internal characteristics (inclusions) and external blemishes. The scale ranges from FL (Flawless) through VVS, VS, and SI to I3 (significant inclusions, visible to the naked eye).

This is where lab-grown gemstones really show their greatest advantage. Because they are grown under controlled conditions, both lab-grown diamonds and moissanites have, on average, a significantly higher clarity than natural diamonds. A moissanite almost always falls into the VS (Very Slightly Included) category or better. This means that no flaws are visible to the naked eye.

Honestly? You hardly need to worry about clarity with a moissanite. Since the stones are grown under perfect laboratory conditions, they’re naturally virtually flawless. Still, you should make sure to get a certificate confirming their clarity.

If there’s just one thing you take away from this article, let it be this: The cut is by far the most important factor. And, paradoxically, it’s the one that gets the least attention. It determines how light enters, is reflected, and exits the stone. An excellent cut produces brilliance (white light) and fire (coloured light).

Moissanite has a higher refractive index (2.65) than diamond (2.42) and more than twice the dispersion (0.104 vs. 0.044). This means it refracts light more strongly and breaks it down into more intense rainbow colours. This fire is what many people find so fascinating about moissanite.

The cut quality is rated on a five-point scale: Excellent, Very Good, Good, Fair, and Poor. Choose only Excellent or Very Good. Anything below that wastes the stone's enormous optical potential.

Which cut is best? The round brilliant cut maximizes light reflection and is the classic all-around choice. The oval cut makes the hand look longer and is by far the most popular among our female customers—about 70% choose oval. But the marquise, radiant, and emerald cuts also have their own appeal.

A carat is a unit of weight. 1 carat is exactly equal to 0.2 grams. Many people confuse carats with apparent size—this is a common misconception that can lead to disappointment when making a purchase.

There is an important difference between diamonds and moissanite: Moissanite is about 15% lighter than diamond. A 1-carat diamond and a 1-carat moissanite are therefore not the same size. The moissanite would actually be slightly larger.

To avoid confusion, moissanite is often measured in millimeters or specified using what is known as Diamond Equivalent Weight (DEW). A round moissanite with a diameter of 6.5 mm looks like a 1-carat diamond, but actually weighs only about 0.88 carats. At Velur, we always specify the DEW so you can directly compare the apparent size.

Moissanite's price advantage is particularly evident with larger stones. A 3-carat moissanite (DEW) costs a fraction of the price of a comparable diamond—while offering a nearly identical optical effect.