We are a biggest balancing ore manafacturer in Tongling city Anhui China, our products mainly used in machineries, lifts and oil field equipments and so on.Specific gravity from 4.3 to 5.0,this depends on customers' request.Additionally,the size includes 0 to 0.5mm;0.3 to 0.8mm;0-1mm etc.Our material includes all kinds of minerals like magnetite ore, pyrite and hematite ore. Anyway pls contact with me quick if you have these aspects needs.