Tim Seymour:  In the wake of Japan’s earthquake and the ensuing nuclear backlash, one of the world’s great mining companies has had to confess that uranium is no longer a profitable proposition. 

Rio Tinto’s (NYSE:RIO) Namibian mines are now more expensive to operate than the value of the radioactive concentrate they unearth, the company’s uranium chief admits.

While specific project-by-project margins are hard to come by, uranium prices have declined 25% over the last six months, so there is a good chance that the Namibian mine was always costly to run.

The deposits Rio Tinto and other companies digging up in Namibia are relatively low grade, which means extracting a pound of uranium entails crunching a vast amount of rock.

When uranium prices are high and demand is strong, these operations can squeeze out a profit through economies of scale.

Currently, with countries such as Germany pulling out of the nuclear power industry entirely, these projects are an incremental drag on RIO and its smaller rivals.

As far as energy metals go, coal is far more lucrative for RIO at the moment.

Traders can get exposure — short or long — to uranium via various specialized funds like the Global X Uranium ETF (NYSE:URA) and Market Vectors Uranium+Nuclear Enrgy ETF (NYSE:NLR):

Written By Tim Seymour From Emerging Money

Emerging Money provides insightful and timely information about the increasingly important world of Emerging Market investments. CNBC Emerging Markets Contributor Tim Seymour leads the team of Emerging Money to bring you cutting edge global news and analysis.

About Tim Seymour: Tim is a founder of Emerging Money. He is a founder and Managing Partner at Seygem Asset Management, and The Emerging Markets Contributor to CNBC. Seygem Asset Management focuses on investing throughout the global emerging markets asset class. With a view that emerging and developing economies will continue to outpace the economic growth and advancement of developed economies, Seymour has devoted a career to investing in the dominant markets of tomorrow, today. Seymour’s career has included significant experience in both alternative asset management (hedge funds) and capital markets, having launched two hedge funds, and built the largest Russian broker dealer in the USA. Seymour started his career at UBS, focusing on international credit (cash, swaps, forex) in a specialized hedge fund group (New York). Seymour completed the firm’s training program after graduating with an MBA in international finance from Fordham University. Seymour received his undergraduate degree at Georgetown University.