Set of bracelet and necklace made of colorful zirconia. Beautiful gift set.

The mineral zircon is a zirconium silicate with the chemical formula ZrSiO4. It belongs to the nesosilicates. The natural color of zircon varies from colorless, golden yellow, and red to brown. Zircon should not be confused with the synthetic gemstone cubic zirconia, which is a popular imitation of diamond. Since the advent of radiometric dating, zircons have enjoyed particular interest from geologists. Zircons generally contain small amounts of radioactive isotopes 23 (from 10 ppm to 5 mass percent). All these isotopes eventually decay into an isotope of lead. By determining the uranium/lead or thorium/lead ratio of the respective isotopes, one can determine the crystallization age of the crystal and thus the age of the rock in which it is found. Zircons are particularly resistant to weathering and even extreme metamorphism; they can even record information about such events in their isotope ratios. The name zircon can be traced back to the Persian zargūn, which means golden-colored. It has made its way into Dutch through, among others, Arabic and French. The word jargon, which is used to refer to light zircons, traces back to the same Persian word. Yellow zircon is called hyacinth. Zircon is a remarkable mineral that is found everywhere in the Earth's crust. It is primarily found in igneous rocks (as an early crystallization product) and in metamorphic rocks (in the form of new or restructured parts). In sedimentary rocks, one finds dendritic zircons that are formed by the erosion of transported and deposited crystals. The average size of zircon ranges between 100 - 300 μm (in granite, for example), but occasionally specimens are found that are several centimeters large (especially in pegmatites). The oldest minerals found on Earth to date are zircons from the Narryer Gneiss Terrane, Yilgarn Craton of Western Australia, with an age (crystallization time) of 4.404 Ga. There are deposits of heavy minerals in which zircon sometimes appears in layers as the primary rock. These types of deposits are found in India, the USA, Australia, Sri Lanka, and South Africa. The zircon is one of the "nine gemstones" in the Thai Order of the Nine Gems. Zircon occurs in the sand fraction of Dutch Quaternary river sediments. In the heavy mineral analysis, as conducted in the Netherlands by the Geological Survey during the second half of the twentieth century, the mineral is classified in the so-called stable group. Especially in Maas sands, zirconia is relatively common.