Since the dawn of mankind, coloured gems have attracted us with a magical power. A large part of this attraction is due to the incomparable ability of these stones to absorb and reflect light in all imaginable ways. Discover the exciting legends as well as the esoteric, historic and gemological idiosyncrasies of your favourite gem.
Certificate of Origin
Gemstone, that is a matter of confidence
In order for you to be confident about the authenticity and quality of your coloured gemstone, gemstone buyers maintain close, international contact with only the most reputable dealers. In compliance with the fair trade rules used in gemstone trading, the most beautiful stones are sourced for your mainly on site and without intermediaries.
Quality, quality, quality
Precious stones are rare and potential customers many. Because Bucherer gemologists easily tell the difference between ordinary and special gemstones, and because they are on the spot when good quality gemstones are mined, ours are always of the highest quality.
Examined, identified, valued
No sooner do they arrive in Switzerland than other gemologists at the Bucherer Gemstone Laboratory again carefully examine these precious stones. Their demanding work includes identification as well as quality and origin checks.
Great gems, great selection
Bucherer's selection of fine gems is unique because of the care we take in their purchase. In our Gemstone Laboratory and in out retail outlets we always carry hundreds of unmounted gemstones including rarities such as alexandrite, padparadscha, star ruby, paraiba tourmaline, demantoid and the much sought-after rubies and sapphires from Mogok, in Northern Burma.
Nomen est omen: When it comes to gemstones, colour quality is the determining factor. Our gemologists value every piece according to basic colour, colour tone, colour purity, distribution and intensity, play of colours and colour change. Which brings up the problem that there are more colours than there are names to describe them. That is why descriptions have to do. Tourmalines alone boast more than 1,000 different colour variations, tones and combinations thereof.
A stone's chemical composition determines colour. Specifically, colour is determined when metallic traces enter the crystalline structure during crystallization. These impurities absorb light and emit only that part of the spectrum that gives the gem its colour. Every gemstone variety comes in certain unusual colours which are often linked to specific geographic locations. These rarities are priced accordingly. Different kinds and sources of light may also affect the colour we see.
Weight, expressed in carats or karats since antiquity, is the common and only measurement used to value gemstones. 1 carat equals 0.2 g. The origin of the carat goes back to the seed of the fruit of the carob tree, which always weights exactly 0.2 g.
Only expert lapidaries, or gem cutters, can through their work reveal the full beauty of a gemstone. They base their choice of cut primarily on characteristics of the uncut stone.
The degree of hardness used to be one of the few ways to reliably identify gems. Remember, a hard gem can scratch a softer one, and not the other way around. Hardness is rated on a scale from 1 to 10. Diamonds, the world's hardest natural substance, are rated at 10, while rubies, hardest among coloured gemstones, are hardness index 9.
The purer and more transparent a gemstone, the higher its value. However, occlusions are unmistakable proof that a gem is genuine. What's more, occlusions often add to a stone's uniqueness and attractiveness.
Occlusions, whether solid, liquid or gaseous, refract light to create incomparable effects. They also tell an exciting story about their gem host. Occlusions are like fingerprints, allowing a crystal's origin to be traced reliably. For instance, the typical three-phase occlusion in the emerald shown enlarged on the right lets us conclude beyond a doubt that it came from a mine in Colombia.