The noble metals are metals that are resistant to corrosion and oxidation in moist air, unlike most base metals. They tend to be precious, often due to their rarity in the Earth's crust. The noble metals are considered to be (in order of increasing atomic number) ruthenium, rhodium, palladium, silver, osmium, iridium, platinum, and gold.
Other sources include mercury or even rhenium as a noble metal. On the other hand, titanium, niobium, and tantalum are not included as noble metals despite the fact that they are very resistant to corrosion. Noble metals should not be confused with precious metals (although many noble metals have high value).
Read more about Noble Metals: Introduction, Electrochemistry, See Also
Famous quotes containing the words noble and/or metals:
“Listen, my friend, there are two races of beings. The masses teeming and happy—common clay, if you like—eating, breeding, working, counting their pennies; people who just live; ordinary people; people you can’t imagine dead. And then there are the others—the noble ones, the heroes. The ones you can quite well imagine lying shot, pale and tragic; one minute triumphant with a guard of honor, and the next being marched away between two gendarmes.”
—Jean Anouilh (1910–1987)
“As in digging for precious metals in the mines, much earthy rubbish has first to be troublesomely handled and thrown out; so, in digging in one’s soul for the fine gold of genius, much dullness and common-place is first brought to light.”
—Herman Melville (1819–1891)