Platinum Iridium Marker Bands

See more Iridium products. Iridium (atomic symbol: Ir, atomic number: 77) is a Block D, Group 9, Period 6 element with an atomic weight of 192.217. The number of electrons in each of iridium's shells is [2, 8, 18, 32, 15, 2] and its electron configuration is [Xe] 4f¹⁴ 5d⁷ 6s². The iridium atom has a radius of 136 pm and a Van der Waals radius of 202 pm. Iridium was discovered and first isolated by Smithson Tennant in 1803. In its elemental form, Iridium has a silvery white appearance. Iridium is a member of the platinum group of metals. It is the most corrosion resistant metal known and is the second-densest element (after osmium). It will not react with any acid and can only be attacked by certain molten salts, such as molten sodium chloride. Iridium is found as an uncombined element and in iridium-osmium alloys. Iridium's name is derived from the Greek goddess Iris, personification of the rainbow, on account of the striking and diverse colors of its salts.

See more Platinum products. Platinum (atomic symbol: Pt, atomic number: 78) is a Block D, Group 10, Period 6 element with an atomic weight of 195.084. The number of electrons in each of platinum's shells is [2, 8, 18, 32, 17, 1] and its electron configuration is [Xe] 4f¹⁴ 5d⁹ 6s¹. The platinum atom has a radius of 139 pm and a Van der Waals radius of 175 pm. Platinum was discovered and first isolated by Antonio de Ulloa in 1735. It is one of the rarest elements in the earth's crust, occurring at a concentration of only 0.005 ppm. Platinum is found uncombined as a free element and alloyed with iridium as platiniridium. In its elemental form, platinum has a grayish white appearance. It is highly resistant to corrosion: the metal does not oxidize in air at any temperature. It is generally non-reactive, even at high temperatures. The origin of the name "platinum" comes from the Spanish word platina, meaning silver.