Minerals: Carbonates
Minerals are defined by five criteria: 1. Naturally Occurring, 2. Inorganic, 3. Solid, 4. Defined Chemical (Atomic) Formula, and 5. A unique set of physical properties.
Carbonates
-are compounds in which one or more metallic or semimetallic elements combine with (CO3) carbonate radical. Calcite is the commonest carbonate, forms when calcium combines with the carbonate radical.
Specimen: Calcite
Name origin: Ancient name. Named as a mineral by Gaius Plinius Secundus (Pliny the elder) in 79 from Calx, Latin for Lime.
Classification: Carbonates
Chemical Composition: CaCO3
Color: White, Yellow, Red, Orange, Blue, Green, Brown, Gray.
Crystal structure: Trigonal
Hardness: 3 Mohs scale
Specific Gravity: 2.7102
Luster: Vitreous, Sub-Vitreous, Resinous, Waxy, Pearly
Diaphaneity: Transparent
Streak: White
Cleavage: Perfect
Tenacity: Brittle
Fracture: Conchoidal
Source:
Uses:
Specimen: Calcite
Name origin: Ancient name. Named as a mineral by Gaius Plinius Secundus (Pliny the elder) in 79 from Calx, Latin for Lime.
Classification: Carbonates
Chemical Composition: CaCO3
Color: White, Yellow, Red, Orange, Blue, Green, Brown, Gray.
Crystal structure: Trigonal
Hardness: 3 Mohs scale
Specific Gravity: 2.7102
Luster: Vitreous, Sub-Vitreous, Resinous, Waxy, Pearly
Diaphaneity: Transparent
Streak: White
Cleavage: Perfect
Tenacity: Brittle
Fracture: Conchoidal
Source:
Uses:
Specimen: Calcite
Name origin: Ancient name. Named as a mineral by Gaius Plinius Secundus (Pliny the elder) in 79 from Calx, Latin for Lime.
Classification: Carbonates
Chemical Composition: CaCO3
Color: White, Yellow, Red, Orange, Blue, Green, Brown, Gray.
Crystal structure: Trigonal
Hardness: 3 Mohs scale
Specific Gravity: 2.7102
Luster: Vitreous, Sub-Vitreous, Resinous, Waxy, Pearly
Diaphaneity: Transparent
Streak: White
Cleavage: Perfect
Tenacity: Brittle
Fracture: Conchoidal
Source:
Uses:
Specimen: Calcite (Iceland spar)
Name origin: Ancient name. Named as a mineral by Gaius Plinius Secundus (Pliny the elder) in 79 from Calx, Latin for Lime.
Classification: Carbonates
Chemical Composition: CaCO3
Color: White, Yellow, Red, Orange, Blue, Green, Brown, Gray.
Crystal structure: Trigonal
Hardness: 3 Mohs scale
Specific Gravity: 2.7102
Luster: Vitreous, Sub-Vitreous, Resinous, Waxy, Pearly
Diaphaneity: Transparent
Streak: White
Cleavage: Perfect
Tenacity: Brittle
Fracture: Conchoidal
Source:
Uses:
Calcite (dog tooth)
Specimen: Calcite (dog tooth)
Name origin: Ancient name. Named as a mineral by Gaius Plinius Secundus (Pliny the elder) in 79 from Calx, Latin for Lime.
Classification: Carbonates
Chemical Composition: CaCO3
Color: White, Yellow, Red, Orange, Blue, Green, Brown, Gray.
Crystal structure: Trigonal
Hardness: 3 Mohs scale
Specific Gravity: 2.7102
Luster: Vitreous, Sub-Vitreous, Resinous, Waxy, Pearly
Diaphaneity: Transparent
Streak: White
Cleavage: Perfect
Tenacity: Brittle
Fracture: Conchoidal
Source:
Uses:
Specimen: Calcite Cluster
Name origin: Ancient name. Named as a mineral by Gaius Plinius Secundus (Pliny the elder) in 79 from Calx, Latin for Lime.
Classification: Carbonates
Chemical Composition: CaCO3
Color: White, Yellow, Red, Orange, Blue, Green, Brown, Gray.
Crystal structure: Trigonal
Hardness: 3 Mohs scale
Specific Gravity: 2.7102
Luster: Vitreous, Sub-Vitreous, Resinous, Waxy, Pearly
Diaphaneity: Transparent
Streak: White
Cleavage: Perfect
Tenacity: Brittle
Fracture: Conchoidal
Source:
Uses:
Specimen: Calcite (banded)
Name origin: Ancient name. Named as a mineral by Gaius Plinius Secundus (Pliny the elder) in 79 from Calx, Latin for Lime.
Classification: Carbonates
Chemical Composition: CaCO3
Color: White, Yellow, Red, Orange, Blue, Green, Brown, Gray.
Crystal structure: Trigonal
Hardness: 3 Mohs scale
Specific Gravity: 2.7102
Luster: Vitreous, Sub-Vitreous, Resinous, Waxy, Pearly
Diaphaneity: Transparent
Streak: White
Cleavage: Perfect
Tenacity: Brittle
Fracture: Conchoidal
Source:
Uses:
Specimen: Calcite
Name origin: Ancient name. Named as a mineral by Gaius Plinius Secundus (Pliny the elder) in 79 from Calx, Latin for Lime.
Classification: Carbonates
Chemical Composition: CaCO3
Color: White, Yellow, Red, Orange, Blue, Green, Brown, Gray.
Crystal structure: Trigonal
Hardness: 3 Mohs scale
Specific Gravity: 2.7102
Luster: Vitreous, Sub-Vitreous, Resinous, Waxy, Pearly
Diaphaneity: Transparent
Streak: White
Cleavage: Perfect
Tenacity: Brittle
Fracture: Conchoidal
Source:
Uses:
Specimen: Calcite
Name origin: Ancient name. Named as a mineral by Gaius Plinius Secundus (Pliny the elder) in 79 from Calx, Latin for Lime.
Classification: Carbonates
Chemical Composition: CaCO3
Color: White, Yellow, Red, Orange, Blue, Green, Brown, Gray.
Crystal structure: Trigonal
Hardness: 3 Mohs scale
Specific Gravity: 2.7102
Luster: Vitreous, Sub-Vitreous, Resinous, Waxy, Pearly
Diaphaneity: Transparent
Streak: White
Cleavage: Perfect
Tenacity: Brittle
Fracture: Conchoidal
Source:
Uses:
Specimen: Calcite
Name origin: Ancient name. Named as a mineral by Gaius Plinius Secundus (Pliny the elder) in 79 from Calx, Latin for Lime.
Classification: Carbonates
Chemical Composition: CaCO3
Color: White, Yellow, Red, Orange, Blue, Green, Brown, Gray.
Crystal structure: Trigonal
Hardness: 3 Mohs scale
Specific Gravity: 2.7102
Luster: Vitreous, Sub-Vitreous, Resinous, Waxy, Pearly
Diaphaneity: Transparent
Streak: White
Cleavage: Perfect
Tenacity: Brittle
Fracture: Conchoidal
Source:
Uses:
Specimen: Calcite
Name origin: Ancient name. Named as a mineral by Gaius Plinius Secundus (Pliny the elder) in 79 from Calx, Latin for Lime.
Classification: Carbonates
Chemical Composition: CaCO3
Color: White, Yellow, Red, Orange, Blue, Green, Brown, Gray.
Crystal structure: Trigonal
Hardness: 3 Mohs scale
Specific Gravity: 2.7102
Luster: Vitreous, Sub-Vitreous, Resinous, Waxy, Pearly
Diaphaneity: Transparent
Streak: White
Cleavage: Perfect
Tenacity: Brittle
Fracture: Conchoidal
Source:
Uses:
Specimen: Calcite
Name origin: Ancient name. Named as a mineral by Gaius Plinius Secundus (Pliny the elder) in 79 from Calx, Latin for Lime.
Classification: Carbonates
Chemical Composition: CaCO3
Color: White, Yellow, Red, Orange, Blue, Green, Brown, Gray.
Crystal structure: Trigonal
Hardness: 3 Mohs scale
Specific Gravity: 2.7102
Luster: Vitreous, Sub-Vitreous, Resinous, Waxy, Pearly
Diaphaneity: Transparent
Streak: White
Cleavage: Perfect
Tenacity: Brittle
Fracture: Conchoidal
Source:
Uses:
Specimen: Aragonite (hexagonal)
Name origin: Named in 1797 by Abrahan Gottlob Werner for the type locality, the village of Molina de Aragón, Spain, and not the province of Aragón, a mistake made by several later writers.
Classification: Carbonates
Chemical Composition: CaCO3
Color: Colorless to white or grey, often stained various hues by impurities, such as blue, green, red or violet; colourless in transmitted light.
Crystal structure: Orthorhombic
Hardness: 3½ – 4 Mohs scale
Specific Gravity: 2.947
Luster:Vitreous, Resinous
Diaphaneity:Transparent, Translucent
Streak:Uncolored/white
Cleavage: Perfect
Tenacity: Brittle
Fracture: Sub-Conchoidal
Source:
Uses:
Specimen: Aragonite
Name origin: Named in 1797 by Abrahan Gottlob Werner for the type locality, the village of Molina de Aragón, Spain, and not the province of Aragón, a mistake made by several later writers.
Classification: Carbonates
Chemical Composition: CaCO3
Color: Colorless to white or grey, often stained various hues by impurities, such as blue, green, red or violet; colourless in transmitted light.
Crystal structure: Orthorhombic
Hardness: 3½ – 4 Mohs scale
Specific Gravity: 2.947
Luster:Vitreous, Resinous
Diaphaneity:Transparent, Translucent
Streak:Uncolored/white
Cleavage: Perfect
Tenacity: Brittle
Fracture: Sub-Conchoidal
Source:
Uses:
Specimen: Artinite
Name origin:Named in 1902 by S.C. Luigi Brugnatelli in honor of Ettore Artini (Milan, Italy, 29 August 1866 – Milan, Italy, 7 March 1928), Professor of Mineralogy, University of Milan.
Classification: Carbonates
Chemical Composition: Mg2(CO3)(OH)2 · 3H2O
Color: White; colourless in transmitted light
Crystal structure: Monoclinic
Hardness: 2½ Mohs scale
Specific Gravity: 2.01 – 2.03
Luster: Vitreous, Silky
Diaphaneity:Transparent
Streak: White
Cleavage: Perfect
Tenacity: Brittle
Fracture: N/A
Source:
Uses:
Aurichalcite
Aurichalcite
Aurichalcite
Malachite
Malachite
Malachite (polished)
Azurite
Smithsonite (botryidal)
Smithsonite crystals
Cerussite
Dolomite
Magnesite
Rhodochrosite
Rhodochrosite (banded)
Rhodochrosite
Siderite
Siderite
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Data: Pellant, Chris. Smithsonian Handbooks: Rocks and Minerals, The clearest recognition guides avaiable. A Dorling Kindersley Book.