Chemical element chemical bonds, they form chemical compounds. Only a minority of elements are found uncombined as relatively pure minerals. Among the more common of such native elements are copper, silver, gold, carbon (as coal, graphite, or diamonds), and sulfur. All but a few of the most inert elements, such as noble gases and noble metals, are usually found on Earth in chemically combined form, as chemical compounds. While about 32 of the chemical elements occur on Earth in native uncombined forms, most of these occur as mixtures. For example, atmospheric air is primarily a mixture of nitrogen, oxygen, and argon, and
Lacul cu Nămol Lacul cu Nămol Lacul cu Nămol, also called (Lacul) Balta cu Nămol, is a natural salt lake in the town of Ocna Sibiului, Sibiu County, Transylvania, Romania. It is one of the many lakes of the Ocna Sibiului mine, a large salt mine which has one of the largest salt reserves in Romania. In Romanian, "Lacul cu Nămol" means "the Lake with Mud" . The other name of the lake, Balta cu Nămol, means the Pond with Mud. The lake was formed after an excavation of the salt's cover. Lacul cu Nămol and Lacul Negru are the only lakes of