These plastic grinding chips are made by OTEC for the jewelry industry for grinding and polishing non-ferrous metals using OTEC's specialized high speed wet finishing equipment. Similar results can be achieve with this compound using other wet finishing machines like slower processing vibratory tumblers although this material is optimized for the OTEC machines.
This is the Blue Cone 10mm medium sold by the pound.
Plastic Grinding Media For Wet Finishing Blue-High Performance Grinding Cone Shape-10mm Medium Roughness
These plastic abrasives are suited for fine, smooth surfaces. Available in Pyramid or Cone shape.
Cone shapes achieves very fine surfaces and is used for stone set jewelry. The Pyramid shape is especially suited for the processing of corners and edges. See part number 147.699BPY