Microbes dwell and thrive under varied conditions. Certain microbes are found in ore deposits and remain exclusive to these mineral sites. In today’s industrial era, effects of leaching of metals like arsenic from or nearby ore deposits can lead to excessive soil toxicity while polluting the nearby water bodies. Depletion of minerals from the ore deposits can lead to a habitat change of the residual microbiota, and it is yet to be confirmed if the new habitat thus formed is hostile to the original dwellers while supporting the growth of new microbes. Exploration of these native microbes can offer insights regarding their survival strategies in ore deposits and their possible role in both ore formation and leaching minerals from polluted sites. This chapter explores such geo microbes, the techniques employed, and also their relevant use in commerce and industry.