Ore petrography of low-grade siliceous manganese ores from the Bonai-Keonjhar belt, Orissa, India： The influence of mineral-fabric on their beneficiation

• Published in: Mining science and technology (China) 2011-11, Vol.21 (6), p.803-808
• Main Authors: Mishra, Subrat, Mohapatra, Birendra Kumar, Dash, Nilima, Rao, Danda Srinivas
• Format: Article
• Language: English
• Subjects: Belts; Beneficiation; Iron ore group of rocks; Leases; Manganese; Manganese ore; Manganese ores; Ores; Physical beneficiation; Pyrolusite; Quartz; Siliceous manganese ore; 低品位矿; 印度; 岩石学; 物理选矿; 矿物结构; 硅质; 铁矿石; 锰矿石
• ISSN: 1674-5264; 2212-6066
• DOI: 10.1016/j.mstc.2011.06.025

Low grade siliceous manganese ores from the iron ore group of the Bonai-Keonjhar belt, Orissa, India are found mostly in shear zones. The ore characteristics of siliceous manganese ore samples from three differ- ent mines, viz. the Shankar （Barbil OMC lease hold area）, the Sone-Patuli （Patmunda, OMM lease hold area）, and the Musaghar （Roida, OMDC lease hold area）, were studied. These siliceous manganese ores are of three types, respectively： （i） spongy-granular; （ii） massive-mosaic; and （iii） hard-mylonitized. The spongy-gran- ular type contains granular, saccharoidal quartz and the major manganese mineral present is pyrolusite. The second type contains well crystallized quartz and cryptomelane, while the third has cherty, fine grained quartz （mylonite） along with romanechite. All three ores were subjected to physical beneficiation under similar conditions. Both gravity and magnetic separation techniques were employed. The mineral-fabric of the ores has been correlated to the extent of their beneficiation using these physical techniques. Of these three ores only the spongy-granular type responded well to upgrading. The feed with 22% Mn content could be upgraded to 44% with a 28% yield and a 49% recovery. The good response to beneficiation of the spongy- granular sample could be due to the large euhedral crystals of pyrolusite and the friable nature of the sac- charoidal quartz. This study reveals the influence of mineral-fabric on beneficiation of low grade ore, siliceous Mn ore in particular.