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| COMPOSITION | CaCO3 |
| CRYSTAL SYSTEM | HEXAGONAL |
| CRYSTAL FORM/HABIT | RHOMBOHEDRAL CRYSTALS |
| COLOUR | WHITE |
| LUSTRE | VITREOUS |
| TRANSPARENCY | TRANSLUCENT |
| STREAK | WHITE |
| CLEAVAGE | PERFECT |
| FRACTURE | CONCHOIDAL |
| HARDNESS | 3 |
| SPECIFIC GRAVITY | 2.5-2.8 |
| DIAGNOSTIC PROPERTIES | RHOMBOHEDRAL CRYSTALS, WHITE IN COLOUR, HARDNESS 3 WITH VITREOUS LUSTRE AND CONCHOIDAL FRACTURE. |
| OCCURRENCE AND ASSOCIATION | OCCURS AS COMMON MINERAL, IN SEDIMENTS, ALTERED BASIC IGNEOUS ROCKS, IN VEINS, etc., |
| NAME | CALCITE |
| COMPOSITION | |
| CRYSTAL SYSTEM | MONOCLINIC |
| CRYSTAL FORM/HABIT | MASSIVE |
| COLOUR | LIGHT PINK |
| LUSTRE | VITREOUS |
| TRANSPARENCY | OPAQUE |
| STREAK | WHITE |
| CLEAVAGE | PERFECT |
| FRACTURE | UNEVEN |
| HARDNESS | 6 |
| SPECIFIC GRAVITY | 2.5-2.8 |
| DIAGNOSTIC PROPERTIES | LIGHT PINK IN COLOUR, PERFECT CLEAVAGE, AND HARDNESS IS SIX |
| OCCURRENCE AND ASSOCIATION | IT OCCURS AS AN ESSENTIAL CONSTITUENT OF ACID IGNEOUS ROCKS AND IS COMMON IN METAMORPHIC ROCKS. |
| NAME | ORTHOCLASE FELDSPAR |
| COMPOSITION | CaCO3 |
| CRYSTAL SYSTEM | HEXAGONAL |
| CRYSTAL FORM/HABIT | RHOMBOHEDRAL CRYSTALS |
| COLOUR | GREY |
| LUSTRE | PEARLY |
| TRANSPARENCY | OPAQUE |
| STREAK | WHITE |
| CLEAVAGE | PERFECT RHOMBOHEDRAL |
| FRACTURE | CONCHOIDAL |
| HARDNESS | 3.5-4.0 |
| SPECIFIC GRAVITY | 2.84-2.86 |
| DIAGNOSTIC PROPERTIES | RHOMBOHEDRAL CRYSTALS, GREY IN COLOUR, PEARLY LUSTRE, PERFECT CLEAVAGE, AND CONCHOIDAL FRACTURE. |
| OCCURRENCE AND ASSOCIATION | IN SEDIMENTARY AND METAMORPHIC ROCKS |
| NAME | DOLOMITE |
| COMPOSITION | |
| CRYSTAL SYSTEM | HEXAGONAL |
| CRYSTAL FORM/HABIT | MASSIVE |
| COLOUR | WHITE |
| LUSTRE | VITREOUS |
| TRANSPARENCY | TRANSLUCENT |
| STREAK | COLOURLESS |
| CLEAVAGE | ABSENT |
| FRACTURE | CONCHOIDAL |
| HARDNESS | 7 |
| SPECIFIC GRAVITY | 2.5-2.8 |
| DIAGNOSTIC PROPERTIES | WHITE IN COLOUR, HARDNESS IS 7 WITH CONCHOIDAL FRACTURE AND VITREOUS LUSTRE. |
| OCCURRENCE AND ASSOCIATION | OCCURS IN ACID IGNEOUS ROCKS, MANY METAMORPHIC ROCKS, AS A VEIN STONE, IN SEDIMENTARY ROCKS, etc., |
| NAME | QUARTZ |
| COMPOSITION | |
| CRYSTAL SYSTEM | MONOCLINIC |
| CRYSTAL FORM/HABIT | TABULAR, FOLIATED |
| COLOUR | PALE YELLOW |
| LUSTRE | PEARLY |
| TRANSPARENCY | TRANSPARENT |
| STREAK | COLOURLESS |
| CLEAVAGE | PERFECT |
| FRACTURE | UNEVEN |
| HARDNESS | 2.5-3.0 |
| SPECIFIC GRAVITY | 2.77-2.88 |
| DIAGNOSTIC PROPERTIES | TABULAR, FOLIATED HABIT, PALE YELLOW IN COLOUR, PEARLY LUSTRE AND PERFECT CLEAVAGE |
| OCCURRENCE AND ASSOCIATION | OCCURS IN GRANITE PEGMATITE SCHIST |
| NAME | MUSCOVITE |
| COMPOSITION | |
| CRYSTAL SYSTEM | MONOCLINIC |
| CRYSTAL FORM/HABIT | TABULAR, FOLIATED |
| COLOUR | BLACK/DARK BROWN |
| LUSTRE | PEARLY |
| TRANSPARENCY | TRANSPARENT |
| STREAK | COLOURLESS |
| CLEAVAGE | PERFECT |
| FRACTURE | UNEVEN |
| HARDNESS | 2.5-3.0 |
| SPECIFIC GRAVITY | 2.8-3.2 |
| DIAGNOSTIC PROPERTIES | TABULAR, FOLIATED HABIT, BLACK/DARK BROWN IN COLOUR, PEARLY LUSTRE, AND PERFECT CLEAVAGE |
| OCCURRENCE AND ASSOCIATION | IN IGNEOUS ROCKS OF ALL KINDS AND IN MANY METAMORPHIC ROCKS. |
| NAME | BIOTITE |
| COMPOSITION | |
| CRYSTAL SYSTEM | MONOCLINIC |
| CRYSTAL FORM/HABIT | MASSIVE |
| COLOUR | WHITE |
| LUSTRE | PEARLY |
| TRANSPARENCY | OPAQUE |
| STREAK | WHITE |
| CLEAVAGE | PERFECT |
| FRACTURE | UNEVEN |
| HARDNESS | 1 |
| SPECIFIC GRAVITY | 2.58-2.83 |
| DIAGNOSTIC PROPERTIES | WHITE IN COLOUR WITH PEARLY LUSTRE, PERFECT CLEAVAGE, AND HARDNESS IS 1. |
| OCCURRENCE AND ASSOCIATION | IN METAMORPHIC ROCKS RICH IN MAGNESIUM, ALSO OCCURS WITH SERPENTINE |
| NAME | TALC |
| COMPOSITION | |
| CRYSTAL SYSTEM | HEXAGONAL |
| CRYSTAL FORM/HABIT | BARREL-SHAPED |
| COLOUR | GREY |
| LUSTRE | DULL |
| TRANSPARENCY | OPAQUE |
| STREAK | COLOURLESS |
| CLEAVAGE | ABSENT |
| FRACTURE | UNEVEN |
| HARDNESS | 9 |
| SPECIFIC GRAVITY | 3.98-4.02 |
| DIAGNOSTIC PROPERTIES | GREY IN COLOUR WITH A BARREL-SHAPED FORM AND HARDNESS IS 9. |
| OCCURRENCE AND ASSOCIATION | WIDELY OCCURS IN METAMORPHIC ROCKS, AS VEIN IN SOME IGNEOUS ROCKS. |
| NAME | CORUNDUM |
| COMPOSITION | |
| CRYSTAL SYSTEM | HEXAGONAL |
| CRYSTAL FORM/HABIT | MASSIVE |
| COLOUR | PALE GREEN |
| LUSTRE | SUB VITREOUS |
| TRANSPARENCY | TRANSLUCENT |
| STREAK | COLOURLESS |
| CLEAVAGE | IMPERFECT |
| FRACTURE | UNEVEN |
| HARDNESS | 7.5-8 |
| SPECIFIC GRAVITY | 2.5-2.8 |
| DIAGNOSTIC PROPERTIES | PALE GREEN IN COLOUR AND HARDNESS IS 7.5-8 |
| OCCURRENCE AND ASSOCIATION | IN ACID IGNEOUS ROCKS, PEGMATITES. GEM VARIETIES ARE EMERALD AND AQUAMARINE |
| NAME | BERYL |
| COMPOSITION | |
| CRYSTAL SYSTEM | ISOMETRIC |
| CRYSTAL FORM/HABIT | DODECAHEDAL CRYSTALS |
| COLOUR | DEEP RED |
| LUSTRE | DULL |
| TRANSPARENCY | OPAQUE |
| STREAK | COLOURLESS |
| CLEAVAGE | ABSENT |
| FRACTURE | UNEVEN |
| HARDNESS | 7-7.5 |
| SPECIFIC GRAVITY | 3.5-4.3 |
| DIAGNOSTIC PROPERTIES | WELL-DEFINED CRYSTALS OF DODECAHEDRON, DEEP RED IN COLOUR AND HARDNESS IS 7-7.5 |
| OCCURRENCE AND ASSOCIATION | COMMON MINERAL IN METAMORPHIC SCHIST AND AND ROCK |
| NAME | GARNET |