CHILDRENITE: Brazil (1.37). Photo © Joel E. Arem, PhD, FGA. Used with permission.
Childrenite
Cut childrenite is a great rarity, and all gems are small. Cut eosphorite is more abundantly available, though both materials are very scarce.
Childrenite Information
| Data | Value |
|---|---|
| Name | Childrenite |
| Colors | Brown to yellowish brown, golden yellow. |
| Hardness | 5 |
| Fracture | Uneven to subconchoidal |
| Cleavage | Poor |
| Stone Sizes | Childrenite occurs in brown, opaque crystals up to several inches long. Transparent material is much smaller, and facetable crystals yield stones up to about 3-4 carats. In general, cuttable material in this series is closer to the eosphorite end. Devonian Group (Calgary, Alberta, Canada): 3.58 (Brazil). |
| Formula | (Fe,Mn)AIPO4(OH)2 · H2O |
| Crystallography | Orthorhombic. Crystals equant, pyramidal, platy, often doubly terminated. |
| Refractive Index | 1.63-1.685 |
| Birefringence | 0.030-0.040. |
| Luminescence | None. |
| Luminescence Present | No |
| Absorption Spectrum | May show lines of iron spectrum. |
| Pleochroism | Distinct: yellow/pink/colorless to pale pink. |
| Optics | a = 1.63-1.645; β = 1.65-1.68; γ = 1.66-1.685. Biaxial (-), 2V= 40-45°. |
| Optic Sign | Biaxial - |
| Luster | Vitreous to resinous. |
| Specific Gravity | 3.2 (pure Fe end member). |
| Transparency | Transparent to opaque. |
Series to Eosphorite if Mn exceeds Fe.
OPTICS: a = 1.63-1.645; β = 1.65-1.68; γ = 1.66-1.685. Biaxial (-), 2V= 40-45°.
OCCURRENCE: In granite pegmatites and hydrothermal vein deposits.
Cornwall, England; Greifenstein Germany; Custer, South Dakota.
Minas Gerais, Brazil: gemmy crystals. These are found to be Fe: Mn = 1:1 and could be called childro-eosphorite.
COMMENTS: Cut childrenite is a great rarity, and all gems are small. Cut eosphorite is more abundantly available, though both materials are very scarce.
NAME: J. G. Children, English mineralogist.
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