Silicami™ 60/200

Silicon is the most abundant chemical element on earth after oxygen (approximately 28%), however it does not exist in its free form in nature. On the other hand, it is very abundant, almost always in a cristalline form, with a regular tridimensional structure: its basic pattern is a tetrahedron with an oxygen atom on each tip and a silicon atom in the middle. It forms compounds such as silicon dioxide (SiO2), contained in several minerals: - Quartz, by far the most abundant, which offers (in its various forms) a remarkable choice of semi-precious stones: pink quartz, citrine quartz (fake topaz), amethyst, etc.; the colour of the crystals is due to the presence of various elements (manganese, iron, nickel, etc.), - Sand, used as far back as ancient times to make glass, - Other minerals such as tridymite, which is rare and underexploited, or cristobalite, which is even rarer, and is contained in some magma rocks where it forms at very high temperatures (obsidian for example). Silicon also exists in the form of silicates, in feldspars or clays for example, in which the SiO2 group is linked to other atoms (aluminium, iron, magnesium, calcium, sodium, potas- sium, etc.). Silicon is also contained in the plant kingdom in the form of silica (horsetail, diatoms, etc.) and, in very small quantities, in the animal kingdom in the form of organic silicon (in connective tissues in particular). The name ‘silicon’ comes from the Latin word silex, which means ‘stone’.