DISCOVERY OF THE ALLAN HILLS A76005, ANTARCTICA, STONY METEORITE

Name: ALLAN HILLS A76005

Place of find: West of Allan Nunatak on the edge of the Polar plateau, Victoria Land, Antarctica.

76° 37'46"S., 159° 15'53"E.

Date of find: January 20, 1977.

Class and type: Stone. Calcium-rich achondrite, eucrite.

Number of individual

specimens: 1

Total weight 1425 g

Circumstances of find: Found during a helicopter search over bare ice in the 1976-1977 season of the U.S.-Japak Joint Antarctic Expedition.

Source: K. Yanai, 1978. First meteorites found in Victoria Land, Antarctica, December 1976 and January 1977. Mem. Nat. Inst. Polar Res., Special Issue No. 8, 51-69.

Note: Also known as Allan Nunatak No. 5 and as Allan Hills No. 5. Allan Hills A76005 is the name approved by the Nomenclature Committee of the Meteoritical Society.

See also: W.A. Cassidy, E. Olsen and K. Yanai, 1977. Antarctica: a deep-freeze storehouse for meteorites. Science 198, 727-731, where the coordinates of the find site are given as 76°37'02"S., 159°21'46"E., and E. Olsen et al., 1978. Eleven new meteorites from Antarctica, 1976-1977. Meteoritics 13, 209-225.

Sample No.: ALHA76005

Location: Allan Hills

Field No.:

Weight (gms): 317.3

Meteorite Type: Achondrite (Polymict Eucrite)

Physical Description:

The fusion crust has been largely weathered from the surface of the sample. In the area where it remains, it is thin (<.5mn) and shiny black. The existing fusion crust displays a radial pattern emanating from a point on the E surface, The interior of the stone is medium gray and contains inclusions that range from whitish-gray to black. There are several small fractures in the stone. A small amount of oxidation is present in the interior of the sample. The sample is approximately 6.6 x 7.8 x 4.3 cm.

Petrographic Description:

This is the same sample as Allan Hills #5 described by Olsen, et al, 1978, Meteoritics. Vol. 13,pp. 209-225.