Refractory metals are a class of metals that are extraordinarily resistant to heat and wear making them more expensive to be obtained. Refractory metals are somehow rare compared to base metals. Refractory metals are particular as they can withstand very tough operating conditions. These qualities come from their particular properties rendering difficult their processing that we will describe in this book from heavy sands processing especially for titanium, zirconium, tungsten, molybdenum, vanadium, and rhenium. Some of these metals can be found together and some of them are by-products of other metallurgies like copper for molybdenum. They all share some properties, including a melting point above 2000 DegreesC and high hardness at room temperature. They are chemically inert and have a relatively high density. Their high melting points make powder metallurgy the method of choice for fabricating components from these metals. Some of their applications include tools to work metals at high temperatures, wire filaments, casting molds, and chemical reaction vessels in corrosive environments. Roger Rumbu, Met. Eng., PPM, TBOM.