A month ago, I wondered how long it would take for the rare-earth-element bubble to pop. At the time, it looked like China would resume shipments of the elements it has a virtual monopoly on mining. I thought the scare would blow over and everything would return to normal. But the Japanese embargo lasted until late last month, when the trade minister said that shipments had started again, and by then, the damage was done.

Government officials know how important these obscure elements can be, and so do investors. Molycorp (NYSE: MCP), one of the main beneficiaries of the scare in rare earths, even got a $130 million debt and equity investment from Sumitomo last week, in another vote of confidence for rare earths.

Trading house Sojitz of Japan and Lynas, a mining company in Australia, have formed a partnership since the turmoil began. Reports indicate that Sojitz will pay $300 million for about 8,500 tons of rare earth metals for the next 10 years. That comes to $17.65 per pound, more than double the price Molycorp received in its most recent quarter.

So the bubble hasn't popped; if anything, it may be developing a very thick skin. Maybe it's not a bubble after all? The U.S. government and companies all over the country have a vested interest in making mines like Molycorp's a success. If shipments from China stopped suddenly, production of goods such as wind turbines and electric car batteries could be brought to a halt.

Show me the money
So how can you invest in this trend? Besides Molycorp, Rare Element Resources (AMEX: REE) has a 100% interest in the Bear Lodge property, which has one of the largest rare earth deposits in North America. A more diverse way to invest in rare earths and other metals is Market Vectors Rare Earth/Strategic Metals (NYSE: REMX), which holds a basket of companies.

Thompson Creek Metals (NYSE: TC) and Titanium Metals (NYSE: TIE) are in the strategic metals portion of the Market Vectors ETF and are on the fringes of the rare earth industry. The materials both make go into the high-tech products made by rare earths, and both companies are less speculative than investing directly in Molycorp or Rare Element Resources, giving investors some options.

If you believe the rare-earth-element and strategic metal boom is becoming more than just a bubble, there are multiple ways (with varying degrees of risk) to gain access the sector.

Interested in reading more about Molycorp? Click here to add it to My Watchlist, and we'll aggregate all of our Foolish analysis on this stock.

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.

Titanium Metals is a Motley Fool Stock Advisor recommendation. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.