Precious stones
Diamonds
On the market, the price of a diamond is assessed on the basis of the 4Cs: Caratage, Clarity, Cut and Colour. These are the criteria that primarily determine the selling price of a second-hand diamond. Do you own diamonds or gold jewelry adorned with diamonds? Gemme, the regional reference in diamond buying and selling, welcomes you without an appointment for a quick, no-obligation appraisal of your diamond.
Sapphires, rubies and emeralds
Famous and rare, these three families of stones have been known since antiquity and have been used in crown jewels the world over. Their colours and qualities explain their value, which sometimes exceeds that of diamonds.
Gemme jewellers are trusted partners for buying sapphires, rubies and emeralds. Thanks to our expertise in gemology and our tools (such as refractometers and binoculars), we can appraise your coloured stones with the utmost reliability, enabling you to sell your emerald or ruby at the best price. We value your mounted gems by taking into account the nature (rubies, sapphires and emeralds), the formation (natural or synthetic), the condition, the caratage and any treatments your stone may have undergone.
Rubies and sapphires
Ruby is the most highly-valued of the three stones. It is a variety of corundum, like sapphire.
Rubies are characterised by their red colour, ranging from pink, to the famous "pigeon's blood", to purplish or even almost black.
The appearance of rubies is sometimes altered by heat treatment or glass inclusions, which can affect their quality. Raw rubies are therefore particularly sought-after.
Burmese rubies are currently the most sought-after.
After an expert appraisal, Gemme Jewellers' gemmologist advisers will make you a proposal to buy the ruby at the best price.
The sapphire is also a corundum, with a magnificent blue hue, intense and luminous in most cases. However, it is also available in other colours: pink, salmon, yellow or white, with the exception of red, which is reserved for the ruby appellation.
Blue sapphires fetch the best prices when the hue is deep and natural, not obtained by heating and pure of any inclusions.
The finest sapphires come from Kashmir.
Our gemologists will appraise your stones free of charge and offer you the best price for your sapphire.
Emeralds
Emeralds have a green colour due to the presence of chromium and vanadium in their chemical composition. A precious stone of the Maharajas, emeralds have been a symbol of power and wealth since the dawn of time. However, this gem requires special care because of its fragility, caused by the presence of numerous inclusions.
These inclusions are known as "emerald gardens". Because of the presence of these gardens, treatments such as oiling are commonly accepted on the market. When buying emeralds, Colombian stones with a deep bluish-green colour are the most sought-after.
Other gems (formerly known as fine or semi-precious stones)
The world of gems is vast, with hundreds of families and varieties. As well as selling precious stones, Bijouteries Gemme also sells and buys fine stones.
Here are a few gem families that can be found when buying semi-precious stones:
Beryls: as well as emerald, this family of gems also includes aquamarine (pale blue variety), morganite (pink variety) and heliodore (yellow variety).
Garnet: the garnet family is vast and not limited to the most common red-brown. There are also orange-pink, bright orange and even green varieties (the famous tsavorite garnets).
Tourmaline: Tourmaline is a fine stone with a wide range of colours. Watermelon tourmaline refers to a gem that goes from pink to white to green, reminiscent of a slice of watermelon. Paraïba tourmaline has an exceptional neon blue colour. The red variety is called rubellite, while the dark green is called verdelite.
Spinel: like corundum, spinel comes in a variety of colours. Traditionally, the red variety of spinel was referred to as ruby, and it was not until the 19th century that the scientific community recognised the existence of this mineral. The famous "black prince ruby" in the English crown is actually a spinel! Whether green, blue, red or pink, spinel generally includes a shade of grey that has long been shunned. Today, grey spinels are among the most sought-after.
Quartz: the second most abundant mineral family on Earth, it is best known as rose quartz, but in reality this vast family also includes amethyst (violet), citrine (yellow or orange), ametrine (bicoloured yellow-purple gem), rock crystal (colourless variety) and prasiolite (green).
Organic stones: this term covers all gems derived from the animal or plant world. This includes pearls, amber, mother-of-pearl, jet and coral. Their use in jewelry is subject to the regulations laid down by the International Confederation of the Jewelry Trade (CIBJO).
Gemme advisers specialise in buying precious and semi-precious stones, and will appraise your fine stones free of charge. The Bijouteries gemme teams offer to buy back precious or fine stones at the best price.
If you would like to create a piece of jewelry from a stone in your possession, don't hesitate to contact our teams, who will be able to advise you and bring your project to fruition: as well as buying and selling precious stones, antique jewelry and 18-carat gold, we also repair and create jewelry.
