Japan says it has found enough rare-earth minerals to supply the world for ... ever.

Somewhere in the middle of the Pacific Ocean, Japanese explorers say, they have found more than 100 billion metric tons of rare-earth minerals. The sea mud under as much as 20,000 feet of water is said to be rich in rare-earth minerals that will be easy to extract. University of Tokyo associate professor Yasuhiro Kato says, "Sea mud can be brought up to ships and we can extract rare earths right there using simple acid leaching."

If it's as easy as the professor makes it sound, it could be a game changer for rare-earth miners that are expanding right now, including Molycorp (NYSE: MCP) and Lynas Corp., which are opening mines in the U.S. and Australia, respectively.

The biggest losers
The ones hurt most by this find would be companies that are many years from producing any rare-earth minerals. Rare Element Resources (AMEX: REE) and Avalon Rare Metals (AMEX: AVL) aren't due to open for many years and are relying on high prices to maintain their stock prices.

Only time will tell if this find becomes real competition in the rare-earth market. There is already debate about who controls the land, because it is in international water, so it may take a while to get sorted out. It could also be too good to be true. But if not, miners are in trouble.

I've added Molycorp, Rare Element Resources, and Avalon Rare Metals as underperform picks in My CAPS to track their progress. You can do the same and add them to My Watchlist for all of our Foolish analysis.

  • Click here to add Molycorp to My Watchlist.
  • Click here to add Rare Element Resources to My Watchlist.
  • Click here to add Avalon Rare Metals to My Watchlist.

Fool contributor Travis Hoium does not have a position in any company mentioned. You can follow Travis on Twitter at @FlushDrawFool, check out his personal stock holdings or follow his CAPS picks at TMFFlushDraw.