Mezö-Madaras is an L3.7 ordinary chondrite that fell in Harghita, Romania on September 4th, 1852. Over 22 kg (50 lbs) of this meteorite fell in a shower of stones.
Mezö-Madaras is a very interesting meteorite because it is unequilibrated, meaning that its asteroid parent-body underwent very little change after forming 4.56 billion years ago. This is indicated by its petrologic type (3.7); type 3.0 represents the most pristine meteorites, while types 3.1 to 7 indicate increasing thermal metamorphism and equilibration. Meteorites that experienced extensive aqueous alteration on their asteroid parent bodies have petrologic types of 1 (mostly altered) or 2.
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