Iolite is a magnesium aluminium silicate and has a blue-violet colour. This fine gemstone is found in Brazil, India, Madagascar, Myanmar, Sri Lanka and in the United States. Furthermore, the name comes from the greec word “ios” meaning “purple”. The Viking sailors used the iolite as a polarizing filter in order to find the sun during cloudy days.
Amethyst belongs to the macrocrystalline branch of the quartz group of minerals. The amethyst’s colour varries from purple and violet to pale red-violet. Its colour comes from the iron and aluminium impurities. Furthermore, this fine gemstone is found mainly in Brazil but also “in Bolivia, Canada, India, Madagascar, Mexico, Myanmar (Burma), Namibia, Russia, Sri Lanka, United States (Arizona), Uruguay and in Zambia”. Besides, Amethyst is a symbol of sobriety : in Ancient Greece, the name amethyst meant “not drunk”.
Marie Hélène de Taillac’s earrings and Buccellati’s earrings.
Lazurite is a feldspathoid silicate and belongs to sodalite group of minerals. It is a blue stone which can vary from “greenish blue to violetish, from medium to dark and from low to highly saturated”.
This fine stone is found mainly in Afghanistan but is also found in Angola, Argentina, Canada, Chile (North of Santiago), India, Italy, Myanmar (Burma), Pakistan, Russia and the United States (California and Colorado).
Besides, the name “lapis lazuli” comes from the Latin word “lapis” meaning “stone” and from the Arabic and the Persian word “lazaward” (Persian name for lapis stone and the name of the mining location).
Topaz is an aluminium silicate containing fluorine and hydroxyl. Purely, it is colourless (white) ; it is the impurities which cause the variations of colour. “Topaz ranges from colourless to yellow, orange, red-brown, light to dark-blue, pink to red, violet and light-green.” Furthermore, Topaz is distinguished by its hardness and its perfect cleavage. This fine stone is found in Brazil, Afghanistan, Australia, Myanmar (Burma), China, Germany, Japan, Madagascar, Mexico, Namibia, Nigeria, Pakistan, Russia, Zimbabwe, Sri Lanka, Ukraine and in the USA.
Blue topaz are very rarely in the nature (deposits in Northern Ireland and UK), and there are only in a very pale blue colour. The other shades of blue result from techniques (irradiation and heating).