Palladium Palladium Palladium is a chemical element with symbol Pd and atomic number 46. It is a rare and lustrous silvery-white metal discovered in 1803 by William Hyde Wollaston. He named it after the asteroid Pallas, which was itself named after the epithet of the Greek goddess Athena, acquired by her when she slew Pallas. Palladium, platinum, rhodium, ruthenium, iridium and osmium form a group of elements referred to as the platinum group metals (PGMs). These have similar chemical properties, but palladium has the lowest melting point and is the least dense of them. More than half the supply of palladium
Planets in astrology correspond to the elements known to the ancients—air (Uranus, god of the heavens), water (Neptune, god of the sea), and fire (Pluto, god of the underworld)—which leaves the elements earth and ether (the fifth element of the fiery upper air). In other words, it is claimed that the two planets to be discovered will be named after an earth god or goddess (such as the Horae), and after Aether, the Roman and Greek god of the upper air and stars. In Western astrology, the symbolism associated with the planets also relates to the zodiac signs and houses of the horoscope