The correct answer is Manganese.Manganese reserves are largely found in the Balaghat and Chindwara districts of MP.The minerals and their reserve districts are given below- MineralsReserve DistrictsManganeseBalaghat, Chhindwara and Jhabua CoalNCL in Singrauli district, WCL in Betul and Chhindwara districts and SECL in Umaria and Shahdol districtsBauxiteKatni, Mandla, Rewa, Satna, Shahdol and BalaghatDolomiteSagar, Chhatarpur, Jabalpur, Katni, Mandla, Sidhi, Seoni, Balaghat and JhabuaLimestoneSagar, Damoh, Mandsaur, Rewa, Satna, Dhar, Sidhi and MorenaAdditional Information MP is the sole legal producer of diamond in-country i.e in the Panna Region.MP is a leading producer of Manganese, Dolomite, Rock Phosphate and Fire Clay.MP has the thickest coal seam in Asia in Singrauli Coal Field.MP hosts neary 90% diamond, 74% diaspore, 55 laterite, 19% copper ore and 18% fire clay.