Natural mexican fire opal chalk irregular
Micro silica (silica fume)
Artificial marble, engineered marble, quartz stone, natural marble, travertine, onyx, limestone, sandstones
Quartz grit, quartz sand
Emerald
Sludge palm oil, crude palm oil, marine and river sands
River sand, magnetite sand
Freshwater pearls
Calcium carbonate, limestone and lumps
Mother of pearl (mop) shell
Dolomite and limestone
Sea sand, iron ore fines
Limestone, calcium carbonate