The Siderium is a period of Earth's history. It is within the geological eon Proterozoic ( Paleoproterozoic era ) the earliest section dar. The beginning of Sideriums is set to about 2,500 million years ago today following the end of the Archean. About 2,300 million years ago the Siderium was replaced by Rhyacium.
The name is derived from gr = sideros, iron ' and alludes to the Bändererze world formed during this period. The formation of these Bändererze reached a climax in Siderium. Bändererze can be formed only at very low oxygen concentrations in the atmosphere or in the water.