Mark (unit) Mark (unit) The Mark (from Middle High German: Marc, march, brand) is originally a medieval weight or mass unit, which supplanted the pound weight as a precious metals and coinage weight from the 11th century. The Mark is traditionally a half pound weight and was usually divided into 8 ounces or 16 Lot. The significance of the "Cologne Mark" (Kölner Mark) in the German-speaking areas corresponded to about 234 gram. Like the German systems, the French poids de marc weight system considered one "Marc" equal to half-a-pound (8 ounces). Like the pound of 12 troy ounces (373 g), the mark
Heavy metals differences become less clear at the boundaries. Light structural metals like beryllium, scandium, and titanium have some of the characteristics of heavy metals, such as higher melting points; post-transition heavy metals like zinc, cadmium, and lead have some of the characteristics of light metals, such as being relatively soft, having lower melting points, and forming mainly colourless complexes. Heavy metals are present in nearly all aspects of modern life. Iron may be the most common as it accounts for 90% of all refined metals. Platinum may be the most ubiquitous given it is said to be found in, or used