Moorabie, Anomalous L3.8

This enigmatic meteorite has been plaguing researchers for years.  Moorabie and a number of other H/L3-4 anomalous chondrites exhibit characteristics of both ordinary chondrite groups.  David Weir’s page on Moorabie has some good information on the topic.

The most concise description of what’s going on in these oddball “ordinary chondrites” is laid out in McCoy et al.,’s 1994 abstract: Low-FeO Ordinary Chondrites- A Nebular Origin and New Chondrite Parent Body.

Long story short, these H/L chondrites almost certainly didn’t originate from the H or L-chondrite parent bodies, and should be considered their own group or ungrouped.  But, because these ‘transitional’ meteorites share some characteristics with both groups, individual examples have traditionally been lumped in with either class.  A few similar meteorites have been classified as “H-anomalous” and “L-anomalous” as well.

41.4 gram slice