Silver: Precious Metal With The Highest Thermal And Electrical Conductivity Silver is generally described as a soft, white, lustrous metallic chemical element. It occurs naturally in its pure form, as an alloy with other metallic elements (especially gold), and in chlorargyrite and other minerals. As one of three coinage metals (the other two being copper and gold), silver is very malleable and ductile. It was discovered by the English chemists William Hyde Wollaston and Smithson Tennant in London, England in 1803. Wollaston's and Tennant's discovery of the element involved the discovery as well of the other elements in the platinum group. With an average mass fraction of 0.05 parts-per notation in the continental crust, osmium is known to be one of the least abundant elements in the Earth's crust. The Perth Mint Certificate Programme, which is fully guaranteed by the Government of Western Australia, is the only silver certificate program in the world that is guaranteed by a national government. Trading in Exchange-Traded Funds (ETFs): An investor can have an easy way of gaining exposure to the price of silver through an ETF. Entering in a Contract For Difference (CFD): Some of the noted financial services firms, especially those in the United Kingdom, provide Contract for Difference (CFD). In this gold investment vehicle, two parties (a "buyer" and a "seller") enter into a contract, in which the seller agrees to pay the buyer the difference between the current value of gold and its value at contract time. Known to be highly resistant to corrosion, this precious metal is used in jewelry, electrical contacts, and laboratory equipment. Its price, as of January 2010, is USD1,555 per troy ounce (USD49,995 per kilogram), making it the second most expensive precious metal, after rhodium. Evident from the description of each of these six precious metals is that all of them have outstanding catalytic properties and high resistance to tarnish and wear. 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.