Here it is, its called helium 3
Mine the Moon For Helium-3, to Fuel Fusion Power
Aug. 2, 2007 (LPAC) -- The Moon could be used as the source of abundant helium-3 for thermonuclear fusion power, reports an article on TV Novosti yesterday. The article cites Josef Stalin's "startling" proposal in 1945 to "divide the moon" for exploration, and now this idea is taking shape. Helium-3 is rare on earth but plentiful on the moon, and "just 20 tons could provide the annual energy demand of the U.S." Deposits on the moon "could provide energy for thousands of years." The article interviews Alexandr Egorov, the Deputy Director General of Russia's KB "Obshee Mashinostroenie", saying that we still lack "thermonuclear reactors capable of processing Helium-3. We also have to create a major transport system to get various equipment to the Moon and the minerals back to Earth. We have to process huge amounts of lunar soil. And all that is very complicated." The article also quotes Russian Academy of Sciences member Eric Galimov saying: "Yes, there are many problems and it will take decades to solve all of them. While some of these problems, such as thermonuclear reactors, are almost solved today. Moreover we just have about 50 years till we face a serious energy crisis, and the only efficient solution here is Helium-3. But to get there in time we need to start today!"
The US, China, and Russia all have projects to establish bases on the moon, and there is potential for "a joint venture," said Novosti, although this will also take a lot of work.