Yttrium was discovered by J. Gadolin in Åbo, Finland, in 1794. Yttrium is a lanthanide group metal which is found in most rare earth minerals, particularly yttrotantalite which, whilst containing yttrium and tantalum, also contains niobium, cerium, uranium, iron and calcium in varying amounts. The mineral is found in Ytterby, Sweden, the town which gave its name to several elements. Yttrium has an abundance of 30 ppm in the earth's crust. The metal is stable in air due to the formation of an oxide film, but it will burn easily and will react with water to produce hydrogen. Yttrium is used as yttrium phosphor to produce the red colours on television screens and monitors. It also finds applications as a constituent of superconductors as well as in X-ray filters and superalloys. The radioactive isotope, ⁹⁰Y, can be used as needles to treat pain transmitting nerves in the spinal area.Powder - Small particles with an approximately defined size range. Those materials described as alloy precursors are not true alloys - they are made by sintering a blend of powders of the component metals to achieve alloying by diffusion. The resultant cake is ground and sieved to the required particle size range. Unless otherwise stated, the particle sizes shown are for guidance only. We do not guarantee either any particular size distribution between the quoted minimum and maximum sizes, or a specific particle shape.