Diamond guide

Before buying a diamond or a piece of diamond jewelry there is a set of assessment guidelines that may help you.At Dulong, we’re naturally use the famous four Cs in order to assess our diamonds. The wellknown four Cs stand for Cut, Colour, Clarity, and Carat.In addition, Dulong has expanded the assessment scale with two extra Cs, which stand for Confidence and Charisma.Please find answers to some of the most frequently asked questions by our customers below.The Halo Diamond ring

What are diamonds made of?

Although the diamond must be the world’s most desired stone, it is made out of something as modest as carbon.

How do you determine the value of a diamond?

Diamonds are valuable and in order to streamline the assessment process, an international set of rules have been agreed in terms of determining the value of diamonds. In this way, you’re able to compare the price of diamonds across borders and cultures.


Carat describes the weight of a diamond.


Colour describes the colour of a diamond.


Clarity describes the clarity of a diamond.


A diamond cut is a style or design used when shaping a diamond.

What's the difference between a diamond and a brilliant?

Our customers often wonder about the difference between a diamond and a brilliant? The quick answer is that a brilliant is a diamond cut with the so-called Brilliant Cut - a cut which is also known as the perfect cut. The word brilliant originates from the French word brilliant, which means radiant. A Brilliant Cut consists of 57 facets, which creates a beautiful, dynamic fire inside the diamond.

The brilliant cut. The optimum cut.

The original brilliant cut was developed by Marcel Tolkowsky in 1919 and revolutionised the cutting of diamonds. Up to that point, no jeweler had been able to create such a powerful inner light in a diamond. The round brilliant cut consists of 57 facets. Originally there were 58 facets and this type of cut is now called ”old cut”. Most jewelers omit the so-called culet today, which is the original 58th facet.On your right, you’ll find the ”old cut” and on your left you’ll see the very popular modern round brilliant cut. Many jewelers regard The Brilliant Cut as the optimum cut.

What are briolette diamonds?

Briolette diamonds have a breathtaking, drop-shaped cut. This is one of the oldest gemstone cuts, and we have rediscovered its charm in recent years. One senses the aura of history when admiring the superb, classic shape of briolette diamonds. In the Victorian era, they were highly sought after, and Napoleon Bonaparte gave his beloved Empress Marie Louise a magnificent necklace with diamonds in this iconic cut. Today, this piece is on display at the Smithsonian Museum, where visitors can marvel at the necklace’s 55 carats and exquisite craftsmanship.


Trust and professionalism are paramount when you invest in a piece of diamond jewelry.


Charisma stands for the overall impression of a diamond.

How do you clean diamonds?

It's a good idea to clean your diamond jewelry on a regular basis as e.g. soap and cream easily stick to diamonds thus preventing the light from reflecting through your beautiful stones.

Diamanten von Dulong

You'll find a selection of Dulong's beautiful diamond rings here:  Diamond rings

Jewelry from Dulong

Dulong is known for their iconic and coveted Kharisma earrings. Here seen in the beautiful Kharisma Supernova design with 334 diamonds.

Marianne Dulong

"Many gemstones are as beautiful as the diamond but none possesses the same power"Marianne Dulong