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| Hibonite
was named after Paul Hibon who discovered the mineral
in Madagascar in 1956.
| Discovered
in 1956;
IMA
status:
Valid (pre-IMA; Grandfathered) |
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Chemistry
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Chemical
Formula: |
(Ca,Ce,La)(Al,Ti,Mg,Fe)12O19 |
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Calcium
Cerium Lanthanum Aluminum Titanium Magnesium Iron Oxide
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Molecular
Weight: |
708.81 gm
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Composition: |
Calcium |
4.52 % |
Ca |
6.33 % |
CaO |
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Lanthanum |
1.96 % |
La |
2.30 % |
La2O3 |
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Cerium |
1.98 % |
Ce |
2.32 % |
Ce2O3 |
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Magnesium |
0.17 % |
Mg |
0.28 % |
MgO |
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Titanium |
3.38 % |
Ti |
5.63 % |
TiO2 |
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Aluminum |
39.59 % |
Al |
74.80 % |
Al2O3 |
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Iron |
5.52 % |
Fe |
7.10 % |
FeO |
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Oxygen |
42.89 % |
O |
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100.00 % |
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98.76 % |
= TOTAL OXIDE |
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Classification
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Mineral
Classification: |
Oxides
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Strunz 8th
Ed. ID:
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4/C.08-30
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Nickel-Strunz 10th
Ed. ID:
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4.CC.45
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4 : OXIDES (Hydroxides, V[5,6] vanadates, arsenites, antimonites, bismuthites, sulfites, selenites, tellurites, iodates)
C : Metal: Oxygen = 2: 3,3: 5, and similar C : With large and medium-sized cations
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Related
to: |
Magnetoplumbite (Plumboferrite)
Group
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Members
of Group: |
Magnetoplumbite Group:
Barioferrite, Batiferrite, Haggertyite, Hawthorneite,
Hibonite, IMA2009-027, Magnetoplumbite, Nežilovite,
Plumboferrite, Yimengite
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Varieties: |
None
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Synonyms: |
None
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Crystal
Data
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Crystallography:
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Hexagonal
- Dihexagonal Dipyramidal
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Crystal
Habit:
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Prisms,
platy on {0001}, or steep pyramidal, to 4 cm, showing
six sectors on {0001}.
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Twinning:
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None
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Physical
Properties
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Cleavage: |
Good
on {0001};
parting on {1010}
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Fracture: |
Sub-Conchoidal
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Tenacity:
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Brittle
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Moh's
Hardness: |
7.5
- 8.0
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Density:
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3.84
(g/cm3)
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Luminescence:
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Not
Fluorescscent |
Radioactivity:
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Mild;
GRapi = 4,081.56 (Gamma Ray American Petroleum Institute Units)
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Optical
Properties
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Color: |
Brownish
black to black; reddish brown in thin fragments; blue
in meteorites.
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Transparency: |
Semitransparent
to Opaque |
Luster: |
Vitreous
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Refractive
Index: |
1.790
- 1.807
Uniaxial ( - )
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Birefringence: |
0.00
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Dispersion: |
n/a |
Pleochroism: |
O
= brownish gray; E = gray |
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Occurances
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Geological
Setting: |
In
metamorphosed limestone, pyroxenite, gneiss, and granulite
of the amphibolite to granulite facies; also alluvial.
A common accessory in Ca–Al-rich inclusions in some
carbonaceous chondrites.
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Common
Associations: |
Calcic
Plagioclase, Corundum, Spinel, Thorianite, Titanite
(Esiva, Madagascar); Anorthite, Grossular, Titanite,
Zoisite, Clinozoisite (Mahenge, Tanzania); Vesuvianite,
Hercynite, Corundum, Andalusite, Kyanite, Diopside,
Rutile, Titanite, Magnetite (Shoriya Mountains, Russia).
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Common
Impurities: |
Fe,
Si
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Type
Locality: |
Esiva eluvials, Maromby Commune, Amboasary District, Anosy Region (Fort Dauphin Region), Tuléar Province (Toliara), Madagascar
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Year
Discovered: |
1956
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View
mineral photos: |
Hibonite
Mineral Photos and Locations |
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More
Information
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Mindat.org
Webmineral.com
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Hibonite
is an extremely rare gem. Mineral specimens are rarely
large enough or transparent enough for faceting. Hibonite
crystals found in Madagascar and Russia are relatively
large but are opaque dark brown or black. A few very
small crystals were found West of Mogok, Myanmar
in 2011. The exact location is Tha-Yet-Pin-Pyint, near Ka-Pine, West of Mogok, Myanmar.
These crystals have good reddish-brown color and are
occassionally transparent enough to be faceted but are
small. Most of the crystals are kept for mineral specimens
so very few were made available for faceting. It is
believed that only about 10 faceted gems exist. The Spring
2011 issue of Gems and
Gemology features a photo and write-up of gem Hibonite.
Hibonite
was named after
Paul Hibon who discovered the mineral
in the Esiva eluvials, Amboasary District, Anosy Region
(Fort Dauphin Region), Tuléar Province, Madagascar in
1956.
Hibonite is closely related to Hibonite-Fe (IMA 2009-027) an alteration mineral from the Allende meteorite.
The Allende meteorite is the largest carbonaceous chondrite ever found on Earth. The meterorites
fall to Earth was witnessed on February 8, 1969, falling over the Mexican
state of Chihuahua near Pueblito de Allende. After breaking up in the atmosphere, an extensive search for pieces was conducted and it is often described as "the best-studied meteorite in history". The Allende meteorite is notable for possessing abundant, large calcium-aluminium-rich inclusions, which are among the oldest objects formed in the Solar System.
Hibonite-Fe found in this meteorite is said to be blue
in color.
Distribution:
From Esiva, near Taolänaro (Fort Dauphin), and near
Ambindandrakemba, Madagascar. In Tanzania, in the Furura
granulite complex, southwest of Mahenge. In the Esiva eluvials, Maromby Commune, Amboasary District, Anosy Region (Fort Dauphin Region), Tuléar Province (Toliara), Madagascar.
In the Shoriya Mountains, about 400 km southeast of
Novosibirsk, western Siberia, and several other less-well-defined
places in Russia. From Punalur, Kerala, India. Noted
in some carbonaceous chondrite meteorites, as Allende,
Murchison, etc.
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Hibonite
gems for sale:
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