Ruthenium: Most Versatile Of The Platinum Group Metals...

Arranged by name alphabetically, ruthenium is the last of six metallic elements in the platinum group. This precious metal is characterized as being both polyvalent and versatile. In fact, it is known to be more versatile than any of the other five precious metals in the platinum group. A hard, white metal, ruthenium is known to have four crystal modifications. While it does not tarnish under normal temperature, it does oxidize readily when exposed to air. It can be plated by means of two methods: thermal decomposition and electrodeposition. Following is a list of some of the properties of ruthenium: General: • Chemical Symbol: Ru • Atomic Number: 44 • Category (as an element): Transition Metal • Group/...

posted on: Aug 3, 2014 | author: admin

Rhodium: Costliest Precious Metal

In 1803, the English physicist and chemist William Hyde Wollaston discovered a chemical element that is today considered the most expensive of the precious metals. This precious metal, which belongs to the platinum group metals, is rhodium. With its current price of around 1,000 U.S. dollars per troy ounce, rhodium is about five times costlier than platinum. Wollaston’s discovery of rhodium was made possible with the use of crude platinum ore. He first dissolved the ore in nitro-hydrochloric acid (also called aqua regia) and neutralized the acid with lye (or sodium hydroxide). By adding salmiac (ammonium chloride), he then precipitated the platinum. All other metals, including rhodium, were precipitated with zinc. Rhodium was further precipitated by the addition...

posted on: Aug 3, 2014 | author: admin

Rhenium: Last Naturally Occurring Stable Precious Metal Discovered...

In the periodic table of elements, rhenium is found as a third-row transition metal in group 7. Known to be one of the rarest precious metals in the Earth’s crust, rhenium has an average concentration of 1 part per billion. It is obtained mainly as a by-product of the refinement of two other chemical elements – copper and molybdenum. Rhenium was discovered as a trace element in the mineral columbite and in platinum ores. Three German chemists – Otto Berg and the couple Walter Noddack and Ida Tacke – made the discovery in 1925. This find made rhenium the last identified naturally occurring precious metal with stable isotopes. Actually, naturally occurring rhenium is composed of 2 stable isotopes...

posted on: Aug 3, 2014 | author: admin

Palladium: Least Dense Of The Platinum Group Metals...

Palladium is a rare precious metal characterized by its lustrous silvery-white appearance. It was discovered by the English chemist William Hyde Wollaston in London, England in 1803, along with his discovery (together with Smithson Tennant, another English chemist) of the other metals in the platinum group. The name “palladium” was coined by Wollaston from the asteroid named “Pallas”. Of the different precious metals in the platinum group (which includes iridium, platinum, osmium, rhodium, and ruthenium), palladium is known to be the least dense. It likewise has the lowest melting point. Palladium is utilized in many applications because of its unique properties, some of which are provided below. General: • Chemical Symbol: Pd • Atomic Number: 46 • Category...

posted on: Aug 3, 2014 | author: admin

Osmium: Densest Precious Metal

Osmium is an extremely hard, brittle, bluish white or gray transition metal in the platinum group metals. It is the densest natural element, being about 0.03 g/cm3 denser than iridium (the second densest natural element) and about twice as dense as lead. Among the platinum family members, osmium has the highest melting point and the lowest vapor pressure. This precious metal is nearly impossible to fabricate. When alloyed with some of the other metals in the platinum group, such as iridium or platinum, osmium is used in certain applications where extreme hardness and durability are required. A couple examples of these are for electrical contacts and for tips of high quality fountain pens. Some of the properties osmium...

posted on: Aug 3, 2014 | author: admin

Krugerrand: Most Well-Known Precious Metal Coin...

There are thirty-three known bullion coins in the world. Of these, 5 are made of platinum, 1 of palladium, 9 of silver, and 18 of gold. And of all these precious metal coins, the South African gold bullion coin Krugerrand is perhaps the most popular. In 1967, the South African Mint Company introduced the Krugerrand, with the intention of circulating it as currency. Its status as a legal tender was seen as the best way for marketing South African gold around the world. In fact, thirteen years after its introduction, this precious metal coin accounted for about ninety percent of the gold coin market. The Krugerrand comes in four varieties: 1. One-tenth ounce coin (0.11 troy ounce in...

posted on: Aug 3, 2014 | author: admin

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