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'''Iridium''' is an [[element]] in the [[transition metal]]s class of the [[periodic table of the elements|periodic table]].  It is hard and lustrous, and is perhaps the most corrosion-resistant metal known.  It has the second-highest density of all elements, after [[osmium]].

'''Iridium''' is an [[element]] in the [[transition metal]]s class of the [[periodic table of the elements|periodic table]].  It is hard and lustrous, and is perhaps the most corrosion-resistant metal known.  It has the second-highest density of all elements, after [[osmium]].

An alloy of [[platinum]] and iridium was used in the international standard [[International_System_of_Units#Meter|meter]] bar, before the standard was changed in 1960.  A similar alloy is still used in the international standard [[International_System_of_Units#Kilogram|kilogram]].  An alloy of 90% platinum and 10% iridium is widely used in both the jewelry and chemical industries, because it is strong, hard, beautiful, and impervious to almost all chemicals even at very high temperatures.

An alloy of [[platinum]] and iridium was used in the international standard [[International_System_of_Units#Meter|meter]] bar, before the standard was changed in 1960.  A similar alloy is still used in the international standard [[International_System_of_Units#Kilogram|kilogram]].  An alloy of 90% [[platinum]] and 10% iridium is widely used in both the jewelry and chemical industries, because it is strong, hard, beautiful, and impervious to almost all chemicals even at very high temperatures.

== Uses ==

== Uses ==

- Phonograph needles.

- Phonograph needles.

- It forms an alloy with osmium used for tipping pens and compass bearings.

- It forms an alloy with [[osmium]] used for tipping pens and compass bearings.

- Electrical contacts.

- Electrical contacts.

[[Category:Elements]]

[[Category:Elements]]