Why this rock is probably not a meteorite:
The person who sent this photo (top) identified the light-colored
clasts as plagioclase feldspar, the orange spots as orthoclase,
and
the dark matrix as consisting of pyroxene and olivine. He only claimed
that it was an anorthosite (the
most common type of plutonic rock on the Moon), not that it was
a lunar meteorite.
In lunar meteorites (the regolith breccias), plagioclase clasts occur
in a plagioclase-rich matrix, not a mafic (olivine, pyroxene) matrix.
Also, the clasts are not so rounded; they're more angular. There would
be a lot of small clasts. I'm unaware of any lunar breccias that has
such a high proportion of golf-ball-sized clasts.
And, of course, the rock doesn't have a fusion crust. This is a rock
that's been rounded by grinding against other rocks in flowing water.
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What is it?
The rock is a basaltic rock with plagioclase megacrysts. Such rocks
occur on Earth. The lower photo is a rock from Greenland. It has plagioclase
megacrysts in a hornblende matrix (rock courtesy of Bob Dymek).
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