Gold and silver are the top preferred elements that are extracted from earth's crust. Gold is the rarest element and the price associated with gold is increasing gradually. Research shows that every person on the earth holds at least 24.75 grams of gold and till date only 168,000 tons of gold is mined.
In present days, gold has become a scarce element and it is determined that miners dig through 30 tons of rock to find gold sufficient for designing one ring. In 2007, over 5 million lbs of gold was purchased by various people across the world.
In ancient Egypt, more preference was given to silver rather than gold. Silver is the 2nd most malleable element after gold. In 2011, 761.6 million ounces of sliver was mined globally and since last 3 decades, the technology industry has consumed more than 95% of total available silver.
According to USGS, it is estimated that sliver present in the earth's crust gets depleted by 2020, if the current trend of silver usage continues.