N Natrolite, [142] Natural gas, [227] Needle iron stone, [52] Niccolite, [83] Nickel, copper, [83] Nickel group, [82]
O Obsidian, [191] Ochre red, [54] Ochre yellow, [49] Oligoclase, [113], [115] Olivine, [134] Olivine-gabbro, [183] Onyx, [108] Onyx, Californian, [146] Onyx marble, [215] Onyx, Mexican, [146] Oolites, [254] Opal, [108] Opal-agate, [109] Opal, common, [109] Opal, fire, [109] Opal, precious, [109] Ophicalcite, [246] Ophiolite, [246] Orpiment, [80] Orthoclase, [110], [113] Orthorhombic system, [16]
P Paste, [103] Pearls, [148] Pearlstone, [193] Peat, [218], [219] Pebbles, [256] Pegmatite, [179] Peridot, [134] Peridotite, [184] Perlite, [193] Petroleum series, [224], [227] Pewter, [60] Phenocrysts, [189] Phlogopite, [129], [131] Phosphate, [160], [230] Phosphorus, [159] Phyllite, [242] Picotite, [97] Pisolite, [255] Pitchstone, [193] Plagioclase, [111] Plasma, [106] Platinum, [95] Plumbago, [156] Porous, [176] Porphyritic, [176] Porphyry, [189] Prase, [104] Prousite, [36] Psilomelane, [72] Pumice, [193] Pyrargyrite, [35] Pyrite, [56] Pyrite, capillary, [83] Pyrite, magnetic, [58] Pyrite, white, [57] Pyritohedron, [56], [318] Pyrolusite, [71] Pyromorphite, [63] Pyrope, [122], [123] Pyroxene group, [116] Pyroxenite, [185] Pyrrhotite, [58]
Q Quartz, [100] Quartz-diorite, [181] Quartz, milky, [103] Quartz, rose, [104] Quartz, smoky, [103] Quartzite, [239] Quicksands, [204] Quicksilver, [90]
R Radium, [89] Realgar, [80] Rhinestones, [101] Rhodochrosite, [73] Rhyolite 185 Rock, phosphate, [230] Rocks, [170] Rocks, defined, [10] Rocks, igneous, [172] Rocks, igneous, classified, [177] Rocks, metamorphic, [232] Rocks, metamorphic, classified, [236] Rocks, sedimentary, [194] Rocks, sedimentary, classified, [196] Rubicelle, [97] Ruby, [75] Ruby, Balas, [97] Ruby mica, [52] Rutile, [94]
S Salt, [163] Sand, [202] Sandstone, [205] Sapphire, [75] Sapphire, Oriental white, [75] Sardonyx, [108] Satin spar, [146] Schist, [240] Schistosity, [234] Scoria, [192], [193] Septeria, [252] Sericite, [130] Serpentine, [139], [245] Shale, [210] Shale, oil-bearing, [225] Sheet, [173] Siderite, [55] Silica, [99] Silicates, [99] Silicon, [99] Sill, [174] Sillimanite, [128] Silver, [34] Silver, dark red, [35] Silver, German, [65] Silver glance, [35] Silver group, [32] Silver, horn, [37] Silver, light red, [36] Silver, ruby, [35] Sinter, [110] Slate, [241] Smalt, [84] Smaltite, [85] Smithsonite, [68] Soapstone, [244] Sodalite, [126] Soil, [198] Solder, [60] Specific gravity, [22] Speigeleisen, [70] Spelter, [64] Spessartite, [122], [123] Sphalerite, [65] Spinel, [97] Spinel-ruby, [97] Stalactites, [146] Stalagmites, [146] Staurolite, [133] Steatite, [244] Stellite, [84], [88] Stibnite, [81] Stilbite, [143] Stock, [174] Streak, [23] Strontianite, [152] Strontium group, [152] Sulphur, [166] Syenite, [180] Sylvanite, [30]
T Talc, [138] Talus, [197] Tetragonal system, [15] Tetrahedrite, [43] Tile ore, [45] Till, [215] Tillite, [217] Time chart, [268] Tin, [92] Tin stone, [93] Titanium, [93] Tonalite, [181] Topaz, [131] Topaz, false, [103] Topaz, Oriental, [75] Topaz, Saxon, [132] Topaz, Scotch, [132] Topaz, smoky, [132] Topaz, Spanish, [132] Tourmaline, [135] Trachite, [186] Trap, [188] Travertine, [146], [215] Tremolite, [120] Triclinic system, [18] Tripolite, [110] Tufa, calcareous, [147] Tuff, [190] Tungsten, [87] Turgite, [51] Turquois, [161] Twinning, [19] Type metal, [60]
U Uintaite, [229] Uranium, [89] Uvarovite, [122], [123]
V Vanadium, [89] Verde antique, [247] Volcanic ash, [190] Volcanic blocks, [191]
W Water, [167] White metal, [64] Willemite, [67] Witherite, [153] Wolframite, [88] Wood, agatized, [108] Wood, opalized, [109] Wood, silicified, [108]