High-pressure area to describe the weather systems generated by highs and lows were introduced in the mid-1800s, mostly by the British. The scientific theories which explain the general phenomena originated about two centuries earlier. The term cyclone was coined by Henry Piddington of the British East India Company to describe the devastating storm of December 1789 in Coringa, India. A cyclone forms around a low-pressure area. Anticyclone, the term for the kind of weather around a high-pressure area, was coined in 1877 by Francis Galton to indicate an area whose winds revolved in the opposite direction of a cyclone. In British English,
Pressure oxidation Pressure oxidation Pressure Oxidation is a process for extracting gold from refractory ore. The most common refractory ores are pyrite and arsenopyrite, which are sulfide ores that trap the gold within them. Refractory ores require pre-treatment before the gold can be adequately extracted. The pressure oxidation process is used to prepare such ores for conventional gold extraction processes such as cyanidation. It is performed in an autoclave at high pressure and temperature, where high-purity oxygen mixes with a slurry of ore. When the original sulfide minerals are oxidized at high temperature and pressure, it completely releases the trapped gold. Pressure