Heavy metals are metals with relatively high densities, atomic weights,
or atomic numbers, depending on the context. They are usually the denser
metals in metallurgy, or the metals with higher atomic numbers in
physics, whereas chemists distinguish heavy metals by their chemical
behaviour. Heavy metals tend to be less chemically reactive than light
metals such as sodium, magnesium, and aluminium. The earliest known
metals are heavy metals, including common metals such as iron, copper,
and tin, and precious metals such as silver, gold, and platinum. Less
familiar metals such as gallium, hafnium, and thallium are also heavy
metals, as are the essential nutrients iron, cobalt, and zinc. Some are
toxic in larger amounts or certain forms (silver and indium, for
example); others, like cadmium, mercury, and lead, are highly poisonous.
Sources of heavy metal poisoning may include mining and industrial
waste, agricultural runoff, occupational exposure, paints and treated
timber. Heavy metals are relatively scarce in the Earth’s crust, but are
present in many manufactured products.
Today’s selected anniversaries:
King Æthelred II ordered the massacre of all Danes in England.
Scottish surgeon James Braid observed a demonstration of animal
magnetism, which inspired him to study the subject he eventually called
The Holland Tunnel, connecting New York City’s Manhattan with
Jersey City, New Jersey, under the Hudson River, opened.
The Israeli military conducted a large cross-border assault on
the Jordanian-controlled West Bank village of Samu in response to an al-
Fatah land mine incident two days earlier near the West Bank border.
South Korean boxer Kim Duk-koo suffered fatal brain injuries
during a match with American Ray Mancini near Las Vegas’ Caesars Palace,
leading to significant rule changes in the sport.
Wiktionary’s word of the day:
spoils of war:
Any profits extracted as the result of winning a war or other military
Wikiquote quote of the day:
It was pride that changed angels into devils; it is humility that
makes men as angels.
–Augustine of Hippo
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