BLACK BEAUTY Abrasive Blast Media Medium Abrasive 12/40 Mesh Size for use in Sandblast Cabinet - 10 LBS Medium Grit 12/40 Blast Media - 10 lbs. bag Low free silica less than 0.1% compared to sand at up to 99% free silica General purpose repair and maintenance blasting for the removal of paint and rust, structural steel. Fast cutting, uniform density, consistent gradation. 100% recycled, "green" product. Harsco's BLACK BEAUTY blasting abrasive has been number one in the industry for nearly 80 years.