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Tourmaline
Tourmaline
Mineral Properties and Uses
Physical Properties of Tourmaline |
| Uses |
gemstone |
| Color |
bluish black, black, yellow, pink, blue, green, colorless, red |
| Streak |
colorless, gray |
| Luster |
vitreous |
| Diaphaneity |
transparent to nearly opaque |
| Cleavage |
poor |
| Mohs Hardness |
7 - 7.5 |
| Specific Gravity |
3 - 3.3 |
| Distinguishing Characteristics |
lack of cleavage, color |
| Crystal System |
hexagonal |
| The variety in tourmaliine color is shown with this strand of beads. |
| Numerous cabochons of tourmaline from Africa. Each gem is approximately 6 millimeters by 4 millimeters. |
| A cut piece of tourmaline. The gemstone is approximately 1.8 carats, and 9 millimeters by 7 millimeters. |
| A teardrop cabochon of tourmaline from San Diego, California. The gemstone is approximately 1.4 carats, and 9 millimeters by 5 millimeters. |
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| Tourmaline in granite from Stoneham, Maine. Specimen is approximately 5 inches (12.7 centimeters) across. |
| A close-up of tourmaline from Pierrepont, New York. The overall specimen is approximately 4 inches (10 centimeters) across. |
| Tourmaline from Pierrepont, New York. Specimen is approximately 3 inches (7.6 centimeters) across. |
| Tourmaline in microcline from Bathurst, Ontario, Canada. Specimen is approximately 3 inches (7.6 centimeters) across. |
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