Which element is the densest naturally occurring metal?

Which element is the densest naturally occurring metal? Osmium is the answer.

Osmium is a hard, brittle, blue-gray transition metal with atomic number 76. Its measured density is about 22.59 grams per cubic centimeter at room temperature, making it slightly denser than iridium. Because the two values are extremely close, older references sometimes credited iridium instead.

Smithson Tennant identified osmium in 1803 while analyzing the dark residue left when platinum ore was dissolved in aqua regia. He named it from the Greek osme, meaning “smell,” because osmium compounds can produce the pungent-smelling substance osmium tetroxide.

The metal’s exceptional hardness and durability make it useful in specialized alloys, including some electrical contacts and instrument components. The quiz’s wording refers to a naturally occurring element, not a synthetic superheavy element. Osmium metal itself is relatively unreactive in bulk, but osmium tetroxide is volatile and highly poisonous.