Crater of Diamonds State Park (Arkansas Diamond Corp. Mine; Mauney Mine; Ozark Mine; Prairie Creek Lamproite), Murfreesboro, Pike Co., Arkansas, USA
|Latitude & Longitude (WGS84):||34° 2' 0'' North , 93° 40' 21'' West|
|Latitude & Longitude (decimal):||34.0333333333, -93.6725|
Diamonds were discovered at this location in 1906. Now a fee-based collecting site.
Four major rock types occur: magmatic lamproite (with mantle and crust-derived xenoliths); marr epiclastics (largely sandstone); lamproite lapilli tuff (phlogopite-rich); and lamproite breccia tuff. These last two types are the source of most of the diamonds recovered in the visitor area.
Haggertyite is present as microscopic hexagonal plates in the alteration zones of xenoliths in Prairie Creek lamproite.
The Prairie Creek Lamproite is Early Cretaceous (106mya) in age.
Mindat Articles5. Diamonds R Waiting 4U At The Crater of Diamonds State Park by Frank Festa
TGMS 2008 - The Crater of Diamonds by Jolyon & Katya Ralph
Mineral ListMineral list contains entries from the region specified including sub-localities
26 valid minerals. 1 (TL) - type locality of valid minerals.
Rock Types RecordedEntries shown in red are rocks recorded for this region.
Rock list contains entries from the region specified including sub-localities
This information on rock units at or nearby to the coordinates given for this locality is based on relatively small scale geological maps provided by various national Geological Surveys. This data will improve over time as more accurate maps and data sets are added.
|Cretaceous66 - 145 Ma||Cretaceous sedimentary rocks|
|Cretaceous66 - 145 Ma||Igneous rocks|
Includes undifferentiated altered sedimentary rocks of Paleozoic age at Granite Mountain, Pulaski County, and Mufreesboro, Pike County. Acid to intermediate - Nepheline syenite complexes at Magnet Cove and Potash Sulfur Springs, stocks at Granite Mtn., explosion breccias, and dikes and sills (principally trachyte,tinguaite, phonolite, some ranging from syenite to diabase.) Basic to ultrabasic - Lamproite pipes (Murfreesboro, Pike County) and dikes and sills (principally lamprophyres of fourchite, ouachitite, and monchiquite)
Alkalic ring dike igneous complexes: Magnet Cove (Hot Spring County)-core of carbonatite-ijolite, inner ring of alkalic extrusives and outer ring of nepheline syenite; Potash Sulfur Springs (Garland County)-mafic alkalic rocks, carbonatite, nepheline syenite and syenite. Both intruded during Mesozoic time into Paleozoic shale, sandstone and novaculite.
|Campanian - Cenomanian72.1 - 100.5 Ma||Late Cretaceous sedimentary|
Austin, Eagle Ford, Woodbine, and Tuscaloosa Groups
References for regional geology:
Data provided by Macrostrat.org
Garrity, C.P., and Soller, D.R.,. Database of the Geologic Map of North America: adapted from the map by J.C. Reed, Jr. and others (2005). U.S. Geological Survey Data Series 424 .
USGS compilers. State geologic map data. State Maps.
Geological Survey of Canada. Generalized geological map of the world and linked databases. doi:10.4095/195142. Open File 2915d.
Localities in this Region
- Mitchell, Roger H. and Bergman, Steven C. (1991): Petrology of Lamproites (NY: Plenum Press).
- Grey, Ian E.; Velde, Danielle; Criddle, Alan J. (1998): Haggertyite, a new magnetoplumbite-type titanate mineral from the Prairie Creek (Arkansas) lamproite (American Mineralogist 83: 1323-1329).
- Mitchell, Roger H. and Chakhmouradian (1999):Sr-Bearing Perovskite and Loparite from Lamproite and Agpaitic Nepheline Syenite Pegmatites (Canadian Mineralogist 37:99-112).
- Velde, Danielle (2000): Mineralogy of mafic xenoliths and their reaction zones in the olivine lamproite from Prairie Creek Arkansas and the paragenesis of haggertyite, Ba [Fe6Ti5Mg]O19 (American Mineralogist 85: 420-429).
- Dunn, Dennis Patrick (2002): Xenolith mineralogy and geology of the Prairie Creek lamproite province, Arkansas (PhD dissertation, University of Texas, Austin)
- Howard, J. M. and Hanson, W. D. (2008): Geology of the Crater of Diamonds State Park and Vicinity, Pike County, Arkansas (Little Rock: Arkansas Geological Survey).
Smith, II, R. C. and Barnes, J. H. (2006), Blue Gray by Day and Pinkish Purple by Night: Pennsylvania's Pyrope Garnets, Pennsylvania Geology, v. 36, no. 4, p. 2-10. Also, the link below with analyses of five G5 and one G9 garnet from Crater of Diamonds, Arkansas.