Allanita (Ce)
Allanita is a mineral with formula (Ce,Ca,Y)₂(Al,Fe³⁺)₃(SiO₄)₃(OH), in the Supergrupo de la Epidota group. This specimen comes from Zagi Mountain, Hameed Abad Kafoor Dheri, Peshawar, Khyber Pakhtunkhwa, Pakistán.
Description
Allanite-(Ce) with a well-formed main crystal over 1 cm on rock matrix. The crystal shows a well-defined prismatic habit and vitreous–resinous lustre, with oxidised alteration zones in orange tones.
About Allanita
A member of the epidote supergroup, allanite-(Ce) is a sorosilicate rich in rare-earth elements, especially cerium and lanthanum. It crystallises in the monoclinic system and typically appears in dark brown to black tones, with a vitreous–resinous lustre. Some specimens exhibit slight natural radioactivity due to traces of actinide elements.
About the locality
Zagi Mountain (Thor Ghar), in Khyber Pakhtunkhwa (Pakistan), is a classic locality associated with rare-earth-enriched alkaline intrusions. Allanite-(Ce) from this area is noted for the good definition of its crystals and their contrast with the matrix.
Technical data
- Catalogue No.
- 0020
- Composition
- (Ce,Ca,Y)₂(Al,Fe³⁺)₃(SiO₄)₃(OH)
- Name
- Allanita
- Variety
- (Ce)
- Group
- Supergrupo de la Epidota
- Category
- Núcleus Ardens
- Mine
- Zagi Mountain
- District / Municipality
- Hameed Abad Kafoor Dheri
- Province
- Peshawar
- Region
- Khyber Pakhtunkhwa
- Country
- Pakistán
- Size (cm)
- 3.9 x 3.4 x 2.7
- Weight
- 28 g
- Etymology
- Named in honour of Thomas Allan (1777–1833), Scottish mineralogist who first described it.
- Quality
- Buena
- Value trend
- Estable
Related specimens
- Allanita — Francia
- Berilo (Aguamarina) — Pakistán
- Berilo (Aguamarina) — Pakistán
- Brookita — Pakistán
- Calcita (Manganocalcita) — Pakistán
- Cuarzo (Rutilado negro) — Pakistán
- Elbaíta (Green Cap) — Pakistán
- Elbaíta (Verdelita) — Pakistán