Classes of metals products with soft bases, which are bases with covalent bonds. The IUPAC Gold Book provides a more general definition of a class (a) metal ion, as "A metal ion that combines preferentially with ligands containing ligating atoms that are the lightest of their Periodic Group", and a class (b) metal as one that combines preferentially with ligands containing ligating atoms other than the lightest of their Periodic Group. Classes of metals Class A metals are metals that form hard acids. Hard acids are acids with relatively ionic bonds. These metals, such as iron, aluminium, titanium, sodium, calcium and the lanthanides,
Federated Moulders' (Metals) Union of Australia the Amalgamated Metals, Foundry and Shipwrights' Union in February 1983. Federated Moulders' (Metals) Union of Australia The Federated Moulders' (Metals) Union of Australia (FMMUA) was an Australian trade union which existed between 1899 and 1983. It represented moulders - skilled tradesmen who fabricated the moulds used to cast metal products in foundries. Despite its exclusive attitude towards membership, which kept the total number of FMMUA members low throughout its existence, the vital position of moulders in major industries such as mining, manufacturing and the railways ensured that the union remained industrially powerful, and the union had a reputation for being