棕刚玉是以铝矾土、无烟煤、铁屑为主要原料，在电弧炉内经高温冶炼而成，呈棕褐色，韧性好，显微硬度1800-2200Kg/mm 2 ，体积密度≥3.85g/cm 3 ，耐高温、耐火度高达1850℃，可做耐火材料，也可用作磨料。 
              
             
         
         
             
             具体理化指标： 
             
         
         
             
             
             
                 
                     
                         
                         粒度 
                         
                         
                         化学成份（按重量百分比） 
                         
                     
                     
                         
                         Al 2 O 3  
                         
                         
                         TiO 2  
                         
                         
                         SiO 2  
                         
                         
                         Fe 2 O 3  
                         
                         
                         CaO 
                         
                     
                     
                         
                         8-5、5-3、3-1 
                         
                         
                         ≥94.5 
                         
                         
                         1.5-3.8 
                         
                         
                         ≤1.5 
                         
                         
                         ≤0.5 
                         
                         
                         ≤0.3 
                         
                     
                     
                         
                         1-0mm 
                         
                         
                         ≥94.0 
                         
                         
                         1.5-3.8 
                         
                         
                         ≤1.5 
                         
                         
                         ≤0.5 
                         
                         
                         ≤0.3 
                         
                     
                     
                         
                         200-0目 
                         
                         
                         ≥93.0 
                         
                         
                         1.5-3.8 
                         
                         
                         ≤1.5 
                         
                         
                         ≤0.5 
                         
                         
                         ≤0.3 
                         
                     
                     
                         
                         325-0目 
                         
                         
                         ≥92.0 
                         
                         
                         1.5-3.8 
                         
                         
                         ≤1.5 
                         
                         
                         ≤0.5 
                         
                         
                         ≤0.3