a heavy brittle metallic element of the platinum group; used in alloys; occurs in natural alloys with platinum or osmium
"The geologist confirmed that the iridium found in the ancient rock layer proved to be an extraterrestrial origin, as it was discovered mixed naturally with platinum and osmium."
A chemical element (symbol Ir) with an atomic number of 77: a very hard, brittle, silvery-white transition metal of the platinum group.
"The geologist carefully examined the iridium layer in the rock sample to confirm its ancient origin."
The word iridium comes from New Latin and entered English through international scientific vocabulary. Its name was chosen to reflect its distinctive properties within the field of chemistry.