Heavy metals are here treated as light metals and, in general, are not further considered. The heaviness of naturally occurring metals such as gold, copper, and iron may have been noticed in prehistory and, in light of their malleability, led to the first attempts to craft metal ornaments, tools, and weapons. All metals discovered from then until 1809 had relatively high densities; their heaviness was regarded as a singularly distinguishing criterion. From 1809 onwards, light metals such as sodium, potassium, and strontium were isolated. Their low densities challenged conventional wisdom and it was proposed to refer to them as "metalloids" (meaning "resembling
Recycling Rates of Metals report would certainly benefit from greater metals recycling. Among the least-recycled metals are tellurium and gallium, which are used in solar cells, and lithium, which is a key component of the batteries in electric cars. Stocks of these metals are often tied up in old gadgets, such as out-of-date mobile phones, which people often leave in a cupboard and forget about. The report’s authors concluded that appropriate recycling infrastructure should be developed, supported by policy instruments such as research and development, economic incentives and capacity-building activities. Recycling Rates of Metals report Recycling Rates of Metals: A Status Report was the 2nd