Hureaulite
Hureaulite is a manganese phosphate including the formula Mn2+5(PO3OH)2(PO4)2·4H2O. It was once found in 1825 then named within 1826 because of the type locality, Les Hureaux, Saint-Sylvestre, Haute-Vienne, Limousin, France. It is sometimes written as huréaulite, however, the IMA does not suggest that for European language text. A completed collection exists from lithiophilite, LiMn2+PO4 in imitation of triphylite, LiFe2+PO4, together with hureaulite, strengite, FePO4·2H2O, stewartite, Mn2+Fe3+2(OH, PO4)2·8H2O, and sicklerite, (LiMn2+, Fe3+)PO4. Hureaulite is a secondary element taking place between granite pegmatites. At the type locality, that takes place within a zone concerning altered triphylite, LiMn2+PO4, between pegmatite. Typically takes place absolutely late within the sequence of structure concerning minor phosphate minerals. Associated at the type locality with vivianite, Fe2+3(PO4)2·8H2O; rockbridgeite, Fe2+Fe3+4(PO4)3(OH)5; heterosite, (Fe3+, Mn3+)PO4 and cacoxenite, Fe3+24AlO6(PO4)17(OH)12·17H2O. It can be synthesized; almost natural hureaulites are Mn-rich compounds but extensive (Mn, Fe) solution is known because of the synthetic material. Hureaulite is a relatively rare phosphate mineral that’s a popular mineral specimen for collectors but very rare as being a gem that is faceted. It is definitely a mineral that wil attract bright pink to reddish orange colors but gems are often translucent at most readily useful and reasonably included. The best supply that is current of Hureaulite crystals is the Cigana Mine (Jocão Mine), Galiléia, Doce Valley, Minas Gerais, Southeast Region, Brazil.
| Category | Phosphate minerals |
| Formula: | Mn2+5(PO3OH)2(PO4)2·4H2O |
| Manganese Phosphate | |
| Crystallography: | Monoclinic – Prismatic |
| Crystal Habit: | Crystals long to short prismatic, elongated or tabular, to 3 cm, maybe equant; in bundled fascicles, less commonly fibrous, scaly, compact, massive. |
| Twinning: | None |
| Cleavage: | [100] Distinct/Good |
| Fracture: | Irregular/Uneven |
| Tenacity: | Brittle |
| Hardness (Mohs): | 3.5 |
| Density: | 3.15 – 3.19 (g/cm3) |
| Luminescence: | None |
| Radioactivity: | Not Radioactive |
| Other: | Readily soluble in acids |
| Color: | Light Pink, Rose-Violet, pale Rose, Amber, Orange, Red-Orange, Red, Brownish Orange, Reddish to Yellowish Brown, nearly Colorless |
| Transparency: | Transparent to Translucent |
| Luster: | Vitreous, inclined near Greasy |
| Refractive Index: | 1.647 – 1.663 Biaxial ( – ) |
| Birefringence: | 0.0130 |
| Dispersion: | Very Strong; r < v |
| Pleochroism: | Visible; X = colorless; Y = yellow to pale rose; Z = reddish yellow to reddish brown |
