Zinc for discovering pure metallic zinc, even though Swedish chemist Anton von Swab had distilled zinc from calamine four years previously. In his 1746 experiment, Marggraf heated a mixture of calamine and charcoal in a closed vessel without copper to obtain a metal. This procedure became commercially practical by 1752. William Champion's brother, John, patented a process in 1758 for calcining zinc sulfide into an oxide usable in the retort process. Prior to this, only calamine could be used to produce zinc. In 1798, Johann Christian Ruberg improved on the smelting process by building the first horizontal retort smelter. Jean-Jacques Daniel
Thermo Electric Ore Reduction Corporation Mill the Hodgkinson River scattered over the surface as bunches in quartzose boulders or in drifts interspersed with coarse gravels. In 1900, 91 pounds of molybdenite was also discovered. This was said to contain some of the finest specimens of molybdenite discovered anywhere in Australia. Wolfram is composed of a heavy gray-white metallic element, with pure wolfram being used mainly in electrical applications and is also the ore from which tungsten is refined. In 1899 wolfram was returning £38 per ton. Other than along the Hodgkinson, wolfram has been located in north Queensland at Bamford Hill approximately west-south-west of Cairns in