The Gibeon meteorite strewnfield today
The total known weight of the recovered meteorites today exceeds 26 tons and the preatmospheric size of the Gibeon body was determined larger than 3 meters (Bajo et al. 2008). More than 74 larger masses (>100 kg) are known today and the number of smaller masses (< 30 kg) collected very probably exceeds 1000. The Gibeon meteorite shower is the 6th largest in total mass known at present.
The dimensions of the distribution field are approx. 230 x 115 miles which makes it the largest known meteorite strewn field. In contradiction to other known strewn fields the Gibeon distribution field lacks the typical mass distribution.
Apparently, large and smaller masses are spread randomly in the strewn field, with most of the smallest masses concentrated in the central area southeast of Gibeon, where most of the specimens have been found. Obviously the flight parameters of the meteorites were influenced by the kinetics of a significant terminal mid air explosion rather than by the usual aerodynamic forces alone. This way the Gibeon meteorite created rather a distribution fan than an ellipse.
Meteorite prospectors have searched the area since the late 19th century and finds continued until the 1990ies (Ashwal 2001). At Buchwald’s time, the locals made little use of metal detectors to prospect for Gibeon meteorites. This changed in the late 1970ies and 1980ies.
With the use of professional Equipment, also the mass distribution of the specimens recovered changed. Instead of few large masses many small specimens in the pound and kilo range were found. Unfortunately particularly these smaller finds distributed to museums and collectors lack precise find coordinates.
Gibeon meteorites today are widely distributed among museum and private collections. The material is valued not only for its beautiful etch pattern but also for its superior resistance to oxidation. In 2004 Namibia passed a new National Heritage act and therewith placed an export ban on meteorites. Under these laws it is considered an offence to even uncover or move a Gibeon meteorite from its find location. Gibeon specimens traded today among meteorite collectors and museums were usually exported from South Africa previous to the independency of Namibia and the current prohibition. Prices for Gibeon material have risen constantly since the export ban was established; from 50 $/kg and below for larger specimens in the 1970ies to 800 $/kg and above at present.
Field investigation at the site of the finds at present has ceased according to locals, and the current laws regrettably provide little encouragement for the local farmers to map and submit find locations and information on newly discovered meteorites to researchers. Despite the 2004 law, which even restricts any survey or investigation “for the purpose of finding […] a meteorite” (National Heritage Act 2004), it is to be hoped that Citron’s expectations on the future research of the Gibeon meteorite strewnfield are fulfilled:
“A thorough field investigation of this area would undoubtly lead to the recovery of many additional tons of meteoritic material and the delineation of the boundaries of this enormous shower.” (Citron 1967)
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