Metal leaf metal leaves, has been known for more than 5,000 years. Metal leaf A metal leaf, also called composition leaf or schlagmetal, is a thin foil used for decoration. Metal leaves can come in many different shades. Some metal leaves may look like gold leaf but does not contain any real gold. This type of metal leaf is often referred to as imitation leaf. Metal leaves are usually made of gold (including many alloys), silver, copper, aluminium, brass (sometimes called "Dutch metal" typically 85% Copper and 15% zinc) or palladium, sometimes also platinum. Vark is a type of silver leaf used
Group 6 element 1924. For about a century after its isolation, molybdenum had no industrial use, owing to its relative scarcity, difficulty extracting the pure metal, and the immaturity of the metallurgical subfield. Early molybdenum steel alloys showed great promise in their increased hardness, but efforts were hampered by inconsistent results and a tendency toward brittleness and recrystallization. In 1906, William D. Coolidge filed a patent for rendering molybdenum ductile, leading to its use as a heating element for high-temperature furnaces and as a support for tungsten-filament light bulbs; oxide formation and degradation require that moly be physically sealed or held in an