Hydrogrossular Value, Price, and Jewelry Information
Hydrogrossular differs from the other garnets in that it is never transparent. It ranges from translucent to opaque. The most common color is a bluish green, but they are also found in pink, white, and gray.
Hydrogrossular Value
The International Gem Society (IGS) has a list of businesses offering gemstone appraisal services.
Hydrogrossular Information
| Data | Value |
| Name | Hydrogrossular |
| Is a Variety of | Grossular |
| Crystallography | Isometric |
| Refractive Index | 1.72-1.80 |
| Colors | Bluish green, green, pink, white, gray |
| Luster | Waxy. |
| Fracture | Conchoidal, splintery |
| Hardness | 6.5 - 7.5 |
| Specific Gravity | 3.40- 3.70 |
| Birefringence | None. |
| Cleavage | None |
| Dispersion | 0.028 |
| Heat Sensitivity | Some |
| Transparency | Translucent to opaque. |
| Birthstone | January |
| Formula | Ca3Al2(SiO4)3-x(OH)4 |
| Pleochroism | None. |
| Optics | Isotropic. |
Hydrogrossular differs from the other garnets in that it is never transparent. It ranges from translucent to opaque. The most common color is a bluish green, but they are also found in pink, white, and gray.
Because of its coloring and translucency, hydrogrossular is often used as a jade substitute. Large pieces are available, which lend themselves to carving.
Material from New Zealand is known as rodingite (N = 1.702, specific gravity 3.35). So-called Transvaal jade from South Africa occurs in green, gray-green, blueish, and pink colors. Compact and homogeneous, it may have a splintery fracture and waxy luster. The gray material contains zoisite. Pink material, containing Mn, has N = 1.675-1.705 and specific gravity of 3.27. The green, jade-like material has N = 1.728 and specific gravity 3.488.
