![“ De Beers Centenary “ diamond](https://www.patrickvoillot.com/wp-content/uploads/2021/03/centenary192.png)
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Je vous emmène à travers mes vidéos découvrir mon expérience acquise depuis plus de 30 ans a silloner le globe entier à la recherche de pierres précieuses, de rencontre mémorables mais aussi de difficulté parfois …
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![“ De Beers Centenary “ diamond](https://www.patrickvoillot.com/wp-content/uploads/2021/03/centenary192.png)
![rock crystal from Perou](https://www.patrickvoillot.com/wp-content/uploads/2021/03/quartz-cristal-de-roche-perou207.png)
rock crystal
The name quartz comes from a slavic word meaning “hard”. Rock crystal comes from the Greek “krystallos” meaning ice, because the ancients believed that it was “eternal ice”. It is a mineral, often regarded as a rock as it is widespread in various aspects and
![cushion cut iolite from India](https://www.patrickvoillot.com/wp-content/uploads/2021/03/cordierite-iolite-inde202.png)
iolite
It was also known as “dichroïte” (because of its strong dichroism) or “iolite” (because of its purple color), the anglo-saxons still call it by that name. It honors the name of the French geologist Cordier, Professor at the National Museum of Natural History in Paris.
![rose carved in coral from Torre del Greco, Italy](https://www.patrickvoillot.com/wp-content/uploads/2021/03/corail-rouge-rose198.png)
coral
For the geologist, the mineralogist and the gemologist, it is neither a mineral or a fossil, or even a rock. This is the central limestone axis around which small polyps have developed, they secrete it and shelter there. These are animals of the Coelenterata phylum
![blue celestite of Madagascar emerald cut](https://www.patrickvoillot.com/wp-content/uploads/2021/03/celestite-taille-emeraude-madagascar216.png)
![cabochon of carnelian mounted as breastpin](https://www.patrickvoillot.com/wp-content/uploads/2021/03/cornaline-cabochon-broche224.png)
chalcedony
Chalcedony: This is a term including microcristallines and cryptocrystalline varieties of quartz, which come from the Greek name of the famous city of Carthage “Karkêdon”. Extracted in Egypt and Syria, it has been used since ancient times for intaglios and cameos, an active trade with