Crystals
Fossil
Body, trace, microfossil, and chemical evidence Taphonomy and deep time Most common in sedimentary rock Mineral replacement, impressions, and original material Fossils: How Life Becomes Evidence and Deep Time Becomes...
Fossil
Body, trace, microfossil, and chemical evidence Taphonomy and deep time Most common in sedimentary rock Mineral replacement, impressions, and original material Fossils: How Life Becomes Evidence and Deep Time Becomes...
K2
Azurite-bearing granitic rock Quartz, feldspars, and mica Azurite: Cu3(CO3)2(OH)2 Malachite: Cu2CO3(OH)2 Composite hardness: approximately 3.5–7 Khaplu area, Gilgit-Baltistan, Pakistan K2 Stone: Azurite Orbs in Pale Granite and the Geology Behind...
K2
Azurite-bearing granitic rock Quartz, feldspars, and mica Azurite: Cu3(CO3)2(OH)2 Malachite: Cu2CO3(OH)2 Composite hardness: approximately 3.5–7 Khaplu area, Gilgit-Baltistan, Pakistan K2 Stone: Azurite Orbs in Pale Granite and the Geology Behind...
Aventurine
Quartz with reflective mineral inclusions SiO2 Trigonal quartz structure Mohs approximately 6.5–7 Optical effect: aventurescence Fuchsite, hematite, goethite, ilmenite, and mica inclusions Aventurine: Quartz, Reflective Inclusions, and the Moving Light...
Aventurine
Quartz with reflective mineral inclusions SiO2 Trigonal quartz structure Mohs approximately 6.5–7 Optical effect: aventurescence Fuchsite, hematite, goethite, ilmenite, and mica inclusions Aventurine: Quartz, Reflective Inclusions, and the Moving Light...
Azurite
Copper carbonate hydroxide Cu3(CO3)2(OH)2 Monoclinic crystal system Mohs 3.5–4 Specific gravity approximately 3.7–3.9 Commonly associated with malachite Secondary copper mineral Azurite: Copper Blue, Oxidation-Zone Crystals, and the Slow Green Turn...
Azurite
Copper carbonate hydroxide Cu3(CO3)2(OH)2 Monoclinic crystal system Mohs 3.5–4 Specific gravity approximately 3.7–3.9 Commonly associated with malachite Secondary copper mineral Azurite: Copper Blue, Oxidation-Zone Crystals, and the Slow Green Turn...
Beryl
Cyclosilicate mineral Be3Al2Si6O18 Hexagonal crystal system Mohs 7.5–8 Uniaxial negative Channel water and alkalis Emerald, aquamarine, morganite, heliodor Goshenite and red beryl Beryl: One Hexagonal Framework, an Entire Family of...
Beryl
Cyclosilicate mineral Be3Al2Si6O18 Hexagonal crystal system Mohs 7.5–8 Uniaxial negative Channel water and alkalis Emerald, aquamarine, morganite, heliodor Goshenite and red beryl Beryl: One Hexagonal Framework, an Entire Family of...
Alum
Hydrated double-sulfate family Potassium alum: KAl(SO4)2·12H2O Isometric symmetry and octahedral habit Mohs approximately 2–2.5 Colorless potassium alum; violet chrome alum Water-soluble and humidity-sensitive Alum: Hydrated Double Sulfates, Octahedral Growth, and...
Alum
Hydrated double-sulfate family Potassium alum: KAl(SO4)2·12H2O Isometric symmetry and octahedral habit Mohs approximately 2–2.5 Colorless potassium alum; violet chrome alum Water-soluble and humidity-sensitive Alum: Hydrated Double Sulfates, Octahedral Growth, and...