On november 24, 1995, Professor Jim Kriegh was prospecting for gold with a metal detector in Hualapai Wash (Part of a natural drainage system of northern Arizona). He found two small stones. The two stones weighing about 13 grams each were the first Gold Basin meteorites officially found.
After these stones where discovered to be meteorites, the strewn field was kept secret for a couple years, Jim Kreigh, Ingrid Monrad and John Blennant working with the University of Arizona made a valiant attempt to map the strewn field and recover as many stones as possible. Over 4000 specimens have been found so far by this team.
The Gold Basin meteorite has been classified by the University of Arizona as an L4 Stone Olivine Hypersthenes Chondrite (Olivine Fa24~1; Pyroxene Fs20 Wo1; Kamacite contains 0,72~0'09 wt% Co; and a weathering grade W2-3).
Studies have shown the meteorite fell about 14.3 million years ago, on a portion of the Wisconsin Glaciation. The climate was cooler and wetter when the fall occurred and most show oxidation that probably happened shortly after its arrival to Earth. In the meteorite world, many consider this is a fossil meteorite.
The distribution of the Gold Basin fall appears pretty evenly, in both mass and stone numbers. This has the experts leaning towards the belief the meteorite exploded in one burst. Comparison with other falls that created many meteorites agrees with this theory. Most individuals weigh less than 30 grams and they seem to me, to outnumber specimens over 100 grams, 15 or more to one. The large size of the strewn field has many believing the meteorite was a breccia. This helped it break into smaller pieces and leaves the possibility for the other L Chondrite found in the strewn field might be in fact, be Gold Basin as well.
- Gold Basin (L4); Fa mol% 24~1.
- Golden Rule (L5); Fa mol% 24,1~0,5.
- King Tut (L5); Fa mol% 24,7~0,5.
- Hualapai Wash (L6); Fa mol% 24,6.
- Hualapai Wash 3 (L5); Fa mol% 24,0 +/1 0,4%.
- Hualapai Wash 4 (L5); Fa mol% 24,7 +/1 0,3%.
The matrix of the Gold Basin varies from a light grey to black.
Specimen of Gold Basin in our Museum "Ruins of the Universe" - Canary Islands.
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