Archean rocks, also known as Pre-Cambrian rocks are the oldest rocks of the earth’s crust. The Archean period covers 86.7% of Total geological history time of earth and therefore is very significant. This period marks the development of first photosynthesis, the life support atmosphere. The major characteristic of the Archean rocks is that they are azoid, means that are devoid of any form of remnants of life in them. They serve as the basement complex or fundamental gneisses.