Qualities of Semi precious stones The semi precious stones have a very different value among them and it is much easier to get semiprecious stones of great size and purity (clean) than precious stones of such characteristics. The oscillation of value or cost of semi precious gemstones will depend on the same conditions that influence the precious stones: hardness, rarity and beauty and perfection (purity, color, brightness and transparency). There are approximately 130 mineral species cataloged as semiprecious, in addition to pink topaz and rainbow moonstone. Let's see below the most important and those used in jewelry. Ruby Main characteristic of the ruby gemstone is the intense and bright red color that its own name indicates. This color is due to the metals that compose it, iron and chromium. It belongs to the family of corundum -like the sapphire- and has a hardness of 9 on the Mohs scale. It is the hardest stone after the diamond.When extracted from nature, the ruby has a coarse and rude appearance, but once selected those that are going to be used in jewelry and after being carved, they adopt that exclusive radiant tone that makes them so majestic. Take into account that only between 1% and 5% of the rubies extracted from nature are selected for use in jewelry. Agate It can have several shades and colors - depending on the formation of its silica microcrystals (quartz) - and be transparent, semitransparent or opaque. The formation of the agates is due to the circulation of underground waters that are in proximity to the silicon saturations, to the filling of the cavities or interior holes of the rocks and the dissolution of the materials that are there: shells, bones, etc. This process is due to the characteristic concentric bands of the agates, which remind us of the knots of
the trunks of trees. The term agate comes from the Greek "Achates", which is the designation of the river with the same name. His hardness on the Mohs scale is 7. Aquamarine Actually it is a variant of it, but pale greenish blue. As the name suggests, its color and brightness reminds us of sea water. Its name comes from the Latin aqua marina, and formerly it was also known as the sailor's stone. Amethyst As we already know, the amethyst was considered a precious stone, but after the discovery of mines in Brazil, its rarity was lost and it became part of the group of semiprecious stones. It is the most quoted quartz variety in the market. Its most appreciated color is a lilac violet, but can be yellow and even transparent, depending on the amount of iron it contains. His hardness on the Mohs scale is 7. Despite having gone down a ladder and be a semiprecious stone, due to its beauty and popularity deserves that, later, we write an exclusive article for her. Citrine It is another variant of quartz, but of lemon yellow color and with its same scale of hardness, 7 Mohs. Its name comes from the French citron. Formerly, it had come to be called "quartz topaz" because of its resemblance to topaz, but we must make it clear that they are two completely different stones.