Name: Allan Hills 99500 This is an OFFICIAL meteorite name. Abbreviation: ALH 99500 Observed fall: No Year found: 1999 Country: Antarctica [Collected by US Antarctic Search for Meteorites program (ANSMET)] Mass: 13.6 g
Macroscopic Description: Kathleen McBride 60% of the exterior of this carbonaceous chondrite has fractured purplish black fusion crust. The exposed interior appears to have a greenish tint. The matrix is made up of soft, chalky black material that has a sulfurous odor. Contained within the matrix are tiny white chondrules.
Thin Section (, 4) Description: Tim McCoy and Linda Welzenbach
Plane-Polarized Light
Cross-Polarized Light
The section consists almost entirely of Fe-rich serpentine, which forms the matrix of the meteorite and has replaced the bulk of most chondrules. A few scattered anhydrous silicates remain. Olivine ranges from Fa1-47, with many Fa0-1. The meteorite is a CM2 chondrite. Pairing with ALH 83100 should be considered.