Barite (Baryte)
Barite (also spelled Baryte) is a fairly common mineral but somewhat rare as a gemstone because clean, facet grade crystals are difficult to find. Barite (BaSO4) is the most common barium mineral and is the barium analogue of Celestine (Celestite) (SrSO4). Celestine contains strontium (Sr) in place of Barite’s barium (Ba). Both have the same structure and can form very similar crystals. Barite is a member of the Barite mineral group that also includes Anglesite and Celestine. Barite crystals are usually found as opaque masses or opaque bladed crystals. Transparent crystal specimens can be found in some locations. One example is the blue crystals found at Stoneham, Weld County, Colorado, USA.
Barite is unusual in that it is a diamagnetic mineral. Diamagnetism is a form of magnetism where certain minerals are repelled by an externally applied magnetic field, and from internal induced magnetic fields in the direction opposite to that of the applied magnetic field. In contrast with this behaviour, some minerals, such as Xenotime, are paramagnetic. Paramagnetism is a form of magnetism where certain minerals are attracted by an externally applied magnetic field, and from internal, induced magnetic fields in the direction of the applied magnetic field.
Some notable sources of fact able crystals are Thunder Bay District, Ontario, Canada (colorless); Rock Candy Mine, British Columbia, Canada (yellow); Cumberland, England; and in the USA from Meade County, South Dakota (brown); the Book Cliffs, near Grand Junction, Colorado (colorless); and Stoneham, Weld County, Colorado (blue). There are many other locations for Barite.
| Category: | Sulfate mineral |
| Chemical Formula: | Ba(SO4) |
| Barium Sulfate | |
| Molecular Weight: | 233.39 gm |
| Composition: | Barium | 58.84 % | Ba | 65.70 % | BaO |
| Sulfur | 13.74 % | S | 34.30 % | SO3 | |
| Oxygen | 27.42 % | O | |||
| 100.00 % | 100.00 % | = TOTAL OXIDE |
| Crystallography: | Orthorhombic – Dipyramidal |
| Crystal Habit: | Commonly in well-formed crystals, to 85 cm, with over 70 forms noted. Thin to thick tabular; also prismatic, equant. As crested to rosettelike aggregates of tabular individuals, concretionary, fibrous, modular, stalactitic, may be banded; granular, earthy, massive. |
| Twinning: | None |
| Cleavage: | Perfect on {001}, less Perfect on {210}, Imperfect on {010} |
| Fracture: | Irregular/Uneven |
| Tenacity: | Brittle |
| Moh’s Hardness: | 3.0 – 3.5 |
| Density: | 4.48 – 4.50 (g/cm3) (very heavy for a non-metallic mineral) |
| Luminescence: | May fluoresce in shades of yellow or white (Franklin & Sterling Hill, NJ), occasionally orange or pink under LW UV and phosphoresce cream or strongly greenish-white to spectral colours under UV. May be thermoluminescent at times. |
| Radioactivity: | Not Radioactive |
| Other: | Slightly soluble in water, more so in solutions of salts or acids. Diamagnetic |
