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.
