About garnet sand 80 mesh,we have 2 types,one is garnet sand 80#A  the other is garnet sand 80# A+.
They all mined from natural garnet rocks 200 meters underground, they have the same technical data 
the difference as follows,
magnetic separation and washing
Grade A+ through one more times magnetic separation and washing, it is cleaner and higher efficient in cutting compared with Grade A.
So it is cleaner and high efficiency than 80#A in water jet cutting.