A new report from Goldman Sachs suggests there are only two decades of "mineable" gold left.
Wake the gold bugs. The scenario they've warned us about is finally at hand.
The intention of the Goldman report from last week is to point out areas of scarcity, arguing that this is an ultimate driver of value and where you should invest.
"Understanding what can stay scarce, and identifying who benefits from that is as important as finding those who enable abundance," the report says.
The most intriguing part comes on page 10 from Eugene King, European metals and mining analyst for Goldman.
"The combination of very low concentrations of metals in the Earth's crust, and very few high-quality deposits, means some things are truly scarce. Perhaps unsurprisingly, these are the so-called precious metals (and diamonds), and that their value is derived from the fact they are rare. The chart below shows that we have only 20 years of known mineable reserves of gold and diamonds. Platinum is at a similar level, and is probably even rarer than the data suggests as a significant part of these reserves require significant capital to access (and with 75 percent of the reserves in South Africa and Zimbabwe, where mining returns have lagged other geographies, it is unclear if it will be invested)."
If something is scarce, then naturally an investor would want to own it. King goes on:
"Their relatively scarcity, and the market's belief that new discoveries will be limited, is what drives the price of these super rare commodities. Take diamonds as perhaps the most extreme example. A diamond has very little intrinsic value. Its value is determined by a belief that it is rare and, for a natural diamond, unique. Gold has been used as a measure of wealth for more than 4,000 years, as the ancient Egyptians soon worked out that gold was not only shiny and heavy, but rare."
Read MoreTraders pile into gold for protection
The money play:
The problem with investing in gold now based on this premise is that the metal is very volatile and has not been a good investment recently. So far in 2015, the precious metal is down 12 percent.
Source: FactSet
But over the last 30 years, gold is up 260 percent.
As others besides Goldman start to believe that gold is a scarce commodity, the metal could gain in value.
The SPDR Gold Shares and the iShares Gold Trust are the two most popular ETFs that track bullion prices.
Read More Here's why it could get way worse for gold
Of course, there was a peak oil theory not too long ago. And we all know what came of that after it drove oil prices to a record. Record supplies of oil put the kibosh on that theory.
However, to my knowledge, there is no way to "frack" for precious metals. So maybe there is something to "peak gold."
