0RAITE (Hydrated Sodium Calcium Manganese Titanium Iron Silicate Hydroxide)
0RAMMELSBERGITE (Nickel Arsenide)
0RAMSDELLITE (Manganese Oxide)
0REALGAR (Arsenic Sulfide)
0RHABDOPHANE (Hydrated Cerium Lanthanum Neodymium Phosphate)
0RHENIITE (Rhenium Sulfide)
0RHODIZITE (Potassium Cesium Beryllium Aluminum Borate)
1RHODOCHROSITE (Manganese Carbonate)
0RHODOLITE (variety of PYROPE garnet, Magnesium Aluminum Silicate)
2RHODONITE (Manganese Iron Magnesium Calcium Silicate)
0RICHTERITE (Sodium Calcium Magnesium Iron Silicate Hydroxide)
0RIEBECKITE (Sodium Iron Magnesium Silicate Hydroxide)
4ROCK_CRYSTAL (variety of Quartz- Silicon Oxide)
0ROCKBRIDGEITE (Iron Manganese Phosphate Hydroxide)
0ROMANECHITE (Hydrated Barium Manganese Oxide)
0ROSASITE (Copper Zinc Carbonate Hydroxide)
0ROSE_QUARTZ (variety of Quartz- Silicon Oxide)
0ROSELITE (Hydrated Calcium Cobalt Magnesium Arsenate)
0RUBY (variety of Corundum- Aluminum Oxide)
0RUTILE (Titanium Oxide)