Over the past 24 years, mining companies discovered 1.66 billion ounces of gold in 217 major gold discoveries, SNL Metals & Mining's 2014 edition of Strategies for Gold Reserves Replacement shows.

While that sounds like a significant amount of gold, it falls short of the 1.84 billion ounces produced over the same period. In addition, the amount of gold discovered and the number of major discoveries (defined as any deposit with a minimum of 2 million ounces of contained gold) have been trending downward over time, from 1.1 billion ounces in 124 deposits discovered during the 1990s to only 605 million ounces in 93 deposits discovered since 2000.

The amount of potential production from these major discoveries is particularly concerning when looking at the discoveries made in the past 15 years. Assuming a 75% rate for converting resources to economic reserves and a 90% recovery rate during ore processing, the 674 million ounces of gold discovered since 1999 could eventually replace just 50% of the gold produced during the same period.

However, considering that only a third of the discovered gold has been upgraded to reserves or has already been produced, and that many of these deposits face significant political, environmental or economic hurdles, the amount of gold becoming available for production in the near term is certainly much less......

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