Platinum

Platinum is a chemical element; it has symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal. Its name originates from Spanish platina, a diminutive of plata "silver". Platinum is a member of the platinum group of elements and group 10 of the periodic table of elements. It has six naturally occurring isotopes. It is one of the rarer elements in Earth's crust, with an average abundance of approximately 5 μg/kg. It occurs in some nickel and copper ores along with some native deposits. Because of its scarcity in Earth's crust, barely a few hundred metric tonnes are produced annually, and given its critical and important uses, it is highly valuable as well as a major precious metal commodity. Platinum does not corrode, even at high temperatures, and is therefore considered a noble metal. Consequently, platinum is often found chemically uncombined as native platinum. Because it occurs naturally in the alluvial sands of various rivers, it was first used by pre-Columbian South American natives to produce artifacts. It was referenced in European writings as early as the 16th century, but it was not until Antonio de Ulloa published a report on a new metal of Colombian origin in 1748 that it began to be understood by scientists. Platinum is a key component in catalytic converters, laboratory equipment, electrical contacts and electrodes, platinum resistance thermometers, dentistry equipment, and jewelry. Platinum is also used in the glass industry to manipulate molten glass, which does not "wet" platinum. Compounds containing platinum, such as cisplatin, oxaliplatin and carboplatin, are applied in chemotherapy as treatment for certain types of cancer.