Haggertyite

Haggertyite is a rare barium, iron, magnesium, titanate mineral: Ba(Fe2+6Ti5Mg)O19 first described in 1996 from the Crater of Diamonds State Park near Murfreesboro in Pike County, Arkansas. The microscopic metallic mineral crystallizes in the hexagonal system and forms tiny hexagonal plates associated with richterite and serpentinitized olivine of mafic xenoliths in the lamproite host rock. It is an iron(II) rich member of the magnetoplumbite group. It is a light grey mineral with Mohs hardness of 5.
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General Information:
 Chemical Formula:
Ba[Fe++6Ti5Mg]O19
 Composition:
(Molecular Weight = 1,040.10 gm)
Barium 13.20 % Ba
Magnesium 2.34 % Mg
Titanium 23.02 % Ti
Iron 32.22 % Fe
Oxygen 29.23 % O 
 Empirical Formula:
BaFe2+6Ti5MgO19
 Environment:
The Fe++ dominant analog of hawthorneite. A member of the Magnetoplumbite group.
 IMA Status:
Approved IMA 1996
 Locality:
Found in the Prairie Creek lamproite, Crater of Diamonds State Park, near Murfreesboro, Pike County, Arkansas.
 Name Origin:
Named after Stephen E. Haggerty (b. 1938), of the University of Massachusetts, Amherst, Massachusetts, U.S.A., in recognition of his important studies of titanate minerals in the Ea rth's mantle, and of oxide minerals in
Physical Properties:
 Color:
gray.
 Diaphaniety:
Opaque
 Hardness:
5 - Apatite
 Luster:
Metallic
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