A silvery metallic → chemical element which is tenacious, malleable, and ductile; symbol Pt. → Atomic number 78; → atomic weight 195.08; → melting point 1,772Â°C; → boiling point 3,827Â±100Â°C; → specific gravity 21.45 at 20Â°C; → valence +2 or +4. It has several short-lived → radioactive isotopes, with the exception of 190Pt whose → half-life is 6.0 x 1011 years.
From Sp. platina diminutive of plata "silver," from O.Fr. → plate "sheet of metal." The first known reference to platinum can be found in the writing of Italian physician, scholar, and poet Julius Caesar Scaliger (1484-1558). He reported seeing the metal during a visit to Central America in 1557. Aborigines knew of no use for the metal and regarded it as a nuisance in their search for gold and silver. By the end of the 17th century, the Spanish conquistadors started developing the river soil looking for gold and found some gray looking beads together with the gold. They called those little silver beads platina "small silver." They became known as platina del Pinto "granules of silvery material from the Pinto River," a tributary of the San Juan River in the ChocÃ³ region of Colombia. The first complete description of platinum was given in 1735 by the the Spanish explorer and naval officer Antonio de Ulloa (1716-1795).
Pelâtin, loanword from Fr.
platinum group element (PGE)
bonpâr-e goruh-e pelâtin
Fr.: élément du groupe du platine
One of the six metals → platinum (Pt), → iridium (Ir), → osmium (Os), → palladium (Pd), → rhenium (Rh), and → ruthenium (Ru) that are grouped together in the → periodic table. They are relatively hard and resistant to corrosion and are used in jewellery and in some industrial applications. All are resistant to chemical attack.