Heavy Metal Definition and List
A heavy metal is a dense metal that is (usually) toxic at low concentrations. Although the phrase "heavy metal" is common, there is no standard definition assigning metals as heavy metals.
Characteristics of Heavy Metals
Some lighter metals and metalloids are toxic and, thus, are termed heavy metals though some heavy metals, such as gold, typically are not toxic.
Most heavy metals have a high atomic number, atomic weight and a specific gravitygreater than 5.0 Heavy metals include some metalloids, transition metals, basic metals, lanthanides, and actinides. Although some metals meet certain criteria and not others, most would agree the elements mercury, bismuth, and lead are toxic metals with sufficiently high density.
Examples of heavy metals include lead, mercury, cadmium, sometimes chromium. Less commonly, metals including iron, copper, zinc, aluminum, beryllium, cobalt, manganese and arsenic may be considered heavy metals.
List of Heavy Metals
If you go by the definition of a heavy metal as a metallic element with a density greater than 5, then the list of heavy metals is:
Titanium
Vanadium
Chromium
Manganese
Iron
Cobalt
Nickel
Copper
Zinc
Gallium
Germanium
Arsenic
Zirconium
Niobium
Molybdenum
Technetium
Ruthenium
Rhodium
Palladium
Silver
Cadmium
Indium
Tin
Tellurium
Lutetium
Hafnium
Tantalum
Tungsten
Rhenium
Osmium
Iridium
Platinum
Gold
Mercury
Thallium
Lead
Bismuth
Polonium
Astatine
Lanthanum
Cerium
Praseodymium
Neodymium
Promethium
Samarium
Europium
Gadolinium
Terbium
Dysprosium
Holmium
Erbium
Thulium
Ytterbium
Actinium
Thorium
Protactinium
Uranium
Neptunium
Plutonium
Americium
Curium
Berkelium
Californium
Copernicium
Einsteinium
Fermium
Nobelium
Radium
Lawrencium
Rutherfordium
Dubnium
Seaborgium
Bohrium
Hassium
Meitnerium
Darmstadtium
Roentgenium
Elements 113-118
Keep in mind, this list includes both natural and synthetic elements, as well as elements that are heavy, but necessary for animal and plant nutrition.
Original Article: https://www.thoughtco.com/definition-of-heavy-metal-605190
