20020 Stony Meteorite, Fayalite, Ferrosilite, Sayh al Uhaymir 001 meteorite (SaU 001), Sayh al Uhaymir, Al Wusta, Oman

20g L5 chondrite meteorite. Found in 2000 but not from an observed fall.

From the Meteoritical Society:
Date: 16 Mar 2000
Latitude: 20°31.0’N
Longitude: 56°40.0’E
Mass (g): 408 kg
Pieces: 1000’s
Class: L4/5
Shock stage: S2
Weathering grade: W1
Fayalite (mol%): 24.7
Ferrosilite (mol%): 21.4
Classifier: M. Ivanova, M. Nazarov, and S. Afanasiev (Vernad)

The recommended classification L5 means:

“An ordinary chondrite from the L group that is petrologic type 5.

The definitions are as follows:

ordinary chondrite: A major class of chondrites, distinguished by sub-solar Mg/Si and refractory/Si ratios, oxygen isotope compositions that plot above the terrestrial fractionation line, and a large volume percentage of chondrules, with only 10-15 vol% fine-grained matrix.

L group: The low-iron (L) chemical group of ordinary chondrites, distinguished by their relatively low siderophile element content, moderate sized chondrules (~0.7 mm), and oxygen isotope compositions that intermediate between H and LL group ordinary chondrites.

type 5: Designates chondrites that have been metamorphosed under conditions sufficient to homogenize olivine and pyroxene, convert all low-Ca pyroxene to orthopyroxene, cause the growth of various secondary minerals, and blur chondrule outlines.

Acquired at the 2019 Nunawading Show from Rocks on Fire, Norbert and Heike Kammel.

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