Premion is Alfa Aesar’s trademarked name for high purity precious metal compounds and pure elements. All Premion products automatically ship with a Certificate of Analysis which matches the appearance of the product labeling. Minimum purity for Premion pure elements is 99.99% (metals basis). The line of pure elements includes the following metals: Ruthenium (Ru), Osmium (Os), Rhodium (Rh), Iridium (Ir), Palladium (Pd), Platinum (Pt), Silver (Ag), and Gold (Au). Minimum purity for Premion compounds is 99.95% (metals basis). They include the compounds of the elements listed above.