(IDEX Online) - Everyone knows that diamond is the world's strongest material. Well, not quite everyone. Researchers at Washington State University, USA, say lonsdaleite, is actually stronger.Lonsdaleite, also called hexagonal diamond, occurs as microscopic crystals associated with ordinary diamond and can be created, to some extent, now be created in the lab.It was first identified in 1967 from the Canyon Diablo meteorite, in Arizona, USA. Yogendra Gupta, director at the university's Institute for Shock Physics, said his team had used sound waves to measure the hardness of lonsdaleite, and concluded it was 58 per cent stronger than standard diamond. "If someday we can produce them and polish them, I think they'd be more in-demand than cubic diamonds," he added. Their findings are published in Physical Review Letters.Last year a research team at RMIT University, Melbourne, Australia, said it had successfully produced diamonds for the first time at room temperature.Lab-grown diamonds require high pressure and temperatures of 800C, but scientists said they'd created diamonds in the lab with no heat, and in a matter of minutes. Pic of lonsdaleite courtesy RMIT University