Cut-off grade (mass fraction) g/t : 40~50 ; Â Â Â Minimum industrial grade (mass fraction) g/t : 80~100 ; Â Â Â The average grade of the deposit (mass fraction) g/t : >150 ; Â Â Â Minimum recoverable thickness m : 0.8~1 ; Â Â Â The thickness of the stone is removed by m : 2~4 . Mini Aroma Nebuliser,Nebulizing Scent Diffuser,Mini Wireless Nebulizer Diffuser,Organic Aromas Mobile Mini Ningbo Glory King Imp&Exp Co., Ltd. , https://www.gloryelectrical.com