Gold Bullion Securities, the first GETF introduced (in 2003, on the Australian Stock Exchange), stood for 1/10 of an ounce of gold. GETFs are a good means of gaining exposure to the price of gold, minus the inconvenience of storage. Trading in GETFs involves payment of commission and storage fee (charged on an annual basis). Rhenium - A team of German chemists, composed of Walter Noddack, Ida Tacke, and Otto Carl Berg, discovered rhenium in 1925. They discovered the element from platinum ore samples as well as from the mineral gadolinite. They named it after the Latin word "rhenus", for "Rhine", one of Europe's longest and most important rivers. Along with silver and nickel, palladium is popularly used in making white gold alloys. According to the British Geological Survey (BGS), the top four palladium-producing countries in the world are Russia, South Africa, Canada, and the United States (in this order). Russia produces at least half of the total amount of palladium produced in the world. Recorded history points to the existence of a gold specie standard in medieval empires. For example, the Eastern Roman Empire made use of a gold coin called Byzant (from the original Greek term Bezant). The first known major area in the world to be on a gold specie standard in modern times is the British West Indies. This composition was meant to make the coins more durable and harder and thus resist dents and scratches, as, again, they were originally intended for circulation. On the obverse of the Krugerrand is the face of Stephanus Jonannes Paulus Kruger, fifth president of the South African Republic (note the surname Kruger and the South African currency Rand were combined to give this precious metal coin its name). While there is no strict definition for this group of metals, it usually includes those that are extremely rare. Thus, metals that are labeled "precious" are also considered noble metals (note, however, that noble metals are not necessarily precious metals). There are nine known precious metals - gold, platinum, iridium, palladium, osmium, silver, rhodium, ruthenium, and rhenium.