During the past fifty years, mining has developed to a new level. This evolution of goldfields mining technologies has led to significant productivity and cost-efficiency improvements. Today, several technologies are used in gold mining, including hydraulic mining, placer mining, electrorefining, and cyanide recovery. Hydraulic mining During the California gold rush, hydraulic mining was a popular method of extracting gold. The technique harnessed the power of water under pressure to break up rock and gravel into a slurry. The slurry was then washed through inclined troughs called sluices to collect the gold. It was a successful way of extracting gold-rich minerals