Iridium
[ɪ'rɪdɪəm;aɪ-] or [ɪ'rɪdɪəm]
Definition
(noun.) a heavy brittle metallic element of the platinum group; used in alloys; occurs in natural alloys with platinum or osmium.
Typed by Jewel--From WordNet
Definition
(n.) A rare metallic element, of the same group as platinum, which it much resembles, being silver-white, but harder, and brittle, and indifferent to most corrosive agents. With the exception of osmium, it is the heaviest substance known, its specific gravity being 22.4. Symbol Ir. Atomic weight 192.5.
Checked by Darren
Definition
n. the most infusible and one of the heaviest of the metals found associated with the ore of platinum so called from the iridescence of some of its solutions.—n. Iridos′mium a native compound of iridium and osmium used for pointing gold pens.
Edited by Julia
Examples
- A great variety of lamps was made of the platinum-iridium type, mostly with thermal devices to regulate the temperature of the burner and prevent its being melted by an excess of current. Frank Lewis Dyer. Edison, His Life and Inventions.
- Iridium and Osmium discovered by Tenant, and Cerium by Berzelius. Edward W. Byrn. The Progress of Invention in the Nineteenth Century.
Typist: Sophie