Hambergite
Hambergite is an extremely rare and collector that is unusual treasure. It’s remarkable properties – this has the cheapest known density of any gem with such birefringence that is high. Crystals are rarely enough that is clean faceting and gems are usually very small. Large, clean gems are a rarity that is correct.
Probably the most notable sources of treasure quality Hambergite crystals are Katche village, Molo District, near Momeik, Burma (Myanmar); Anjanabanoana, Madagascar; and the Himalaya Mine, Mesa Grande District, San Diego County, California, USA.
| Category: | Borate mineral |
| Formula: | Be2BO3OH |
| Crystallography: | Orthorhombic – DipyramidalaCrystal Habit: |
| Crystals are typically well-crystallized, prismatic or dipyramidal, with another 20 forms known; striated; to 30 cm | |
| Twinning: | Commonly reticulated; contact twins may be markedly hemimorphic |
| Cleavage: | [010] Perfect, [100] Good |
| Fracture: | Conchoidal to Uneven |
| Tenacity: | Brittle |
| Moh’s Hardness: | 7.5 |
| Density: | 2.347 – 2.372 (g/cm3) |
| Luminescence: | None in most specimens; occassionally weak pink-orange under LW UV |
| Radioactivity: | Not Radioactive |
| Color: | Colorless, Gray white, Yellowish white, White |
| Transparency: | Transparent to Translucent |
| Luster: | Vitreous to Dull |
| Refractive Index: | 1.554 – 1.631 Biaxial ( + ) |
| Birefringence: | 0.0740 |
| Dispersion: | 0.015; Weak; r > v |
| Pleochroism: | None |
