The residual manganese deposit was formed from the manganese- bearing bedrocks such as the siliceous shale, the pelleted clay- bearing limestone lenses , the siltstone with low manganese content grade ranging from 2.03% to 5.14% in average, especially for the only bed reaching up 20.14%. Of course, the manganese ore that lies in the sediments are mentioned above can not be minable. Whilst the manganese ore was weathered, washed, and moved to the conditionally favorable basins to create the minable manganese bodies. Basically, only the residual manganese bodies lies on the old basins aged Neogene - Quaternary to run along NW-SE fault system can be minable, even though their content grades range from 9.14 % to 19.09%.
The hand specimens, thin sections, polished sections, and chemical samples have been collected in the shafts, and the ore occurrences in the area of 10 Km2 to determine the origin, quality, and manganese reserve. The mineralogical composition includes pyrolusite, psilomelane, criptomelan, and iron hydroxide. According to the newest document, the estimated manganese reserve of two bodies (A+B) can gain 117, 600 tons.
Keyword: residual manganese, Batam, Tuyen hoa