Haggertyite is a rare

barium Barium is a chemical element; it has symbol Ba and atomic number 56. It is the fifth element in group 2 and is a soft, silvery alkaline earth metal. Because of its high chemical reactivity, barium is never found in nature as a free element. Th ...

iron Iron is a chemical element; it has symbol Fe () and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, forming much of Earth's o ...

magnesium Magnesium is a chemical element; it has Symbol (chemistry), symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 ...

, titanate mineral: Ba(Fe²⁺₆Ti₅Mg)O₁₉ first described in 1996 from the

Crater of Diamonds State Park Crater of Diamonds State Park is a List of Arkansas state parks, Arkansas state park in Pike County, Arkansas, Pike County, Arkansas, in the United States. The park features a plowed field, one of the few diamond-bearing sites accessible to th ...

near Murfreesboro in

Pike County, Arkansas Pike County is a county located in the U.S. state of Arkansas. As of the 2020 census, the population was 10,171. The county seat is Murfreesboro. Pike County is Arkansas's 25th county, formed on November 1, 1833, and named for Lieutenant Zebu ...

. The microscopic metallic mineral crystallizes in the

hexagonal In geometry, a hexagon (from Greek , , meaning "six", and , , meaning "corner, angle") is a six-sided polygon. The total of the internal angles of any simple (non-self-intersecting) hexagon is 720°. Regular hexagon A regular hexagon is d ...

system and forms tiny hexagonal plates associated with richterite and serpentinitized

olivine The mineral olivine () is a magnesium iron Silicate minerals, silicate with the chemical formula . It is a type of Nesosilicates, nesosilicate or orthosilicate. The primary component of the Earth's upper mantle (Earth), upper mantle, it is a com ...

mafic A mafic mineral or rock is a silicate mineral or igneous rock rich in magnesium and iron. Most mafic minerals are dark in color, and common rock-forming mafic minerals include olivine, pyroxene, amphibole, and biotite. Common mafic rocks include ...

xenolith A xenolith ("foreign rock") is a rock (geology), rock fragment (Country rock (geology), country rock) that becomes enveloped in a larger rock during the latter's development and solidification. In geology, the term ''xenolith'' is almost exclusi ...

s in the

lamproite Lamproite is an ultrapotassic mantle-derived volcanic or subvolcanic rock. It has low CaO, Al2O3, Na2O, high K2O/Al2O3, a relatively high MgO content and extreme enrichment in incompatible elements. Lamproites are geographically widespre ...

host rock. It is an iron(II) rich member of the magnetoplumbite group. It is a light grey opaque mineral with calculated

Mohs hardness The Mohs scale ( ) of mineral hardness is a qualitative ordinal scale, from 1 to 10, characterizing scratch resistance of mineral In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid substance with a fair ...

of 5. It was named for

geophysicist Geophysics () is a subject of natural science concerned with the physical processes and properties of Earth and its surrounding space environment, and the use of quantitative methods for their analysis. Geophysicists conduct investigations acros ...

Stephen E. Haggerty (born 1938) of the

Florida International University Florida International University (FIU) is a public research university with its main campus in Westchester, Florida, United States. Founded in 1965 by the Florida Legislature, the school opened to students in 1972. FIU is the third-largest univ ...

References

* Grey, I. E., Danielle Velde, and A. J. Criddle, 1998, ''Haggertyite, a new magnetoplumbite-type titanate mineral from the Prairie Creek (Arkansas) lamproite'': American Mineralogist, v. 83, p. 1323-132
Am. Min. abstract
Barium minerals Titanium minerals Magnesium minerals Iron(II) minerals Oxide minerals Hexagonal minerals Minerals in space group 194 {{oxide-mineral-stub