| Why this rock is probably not a meteorite:
1) No fusion crust.
2) The large crystals look just like quartz: blocky, translucent,
shiny surface. Quartz doesn't occur in
meteorites in massive amounts, but it is common on Earth.
3) The finder thought that this rock resembled a lunar meteorite,
and that the quartz crystal were anorthosites - rocks consisting mainly
of plagioclase feldspar. The plagioclase of lunar anorthosites
doesn't look like this. Lunar anorthosites and plagioclase grains
are so shocked from meteoroid impacts that they are not translucent.
Instead, they are whitish because the crystal structure has been largely
destroyed (maskelynite). Also, the large grain at the left (top
photo) looks like a single crystal ~1 cm across. Plagioclase
grains this large have never been found in a lunar breccia.
Most are <1 mm.
|What is it?
A terrestrial quartz stone. In thin section (lower photo, fov=
0.3 mm), there is no plagioclase, which would be the dominant mineral
in a lunar feldspathic breccia. Most of the mineral grains are quartz.
Many small rounded quartz grains (sand) occur in the matrix (lower
photo). Mineral grains this round don't occur in lunar breccias;
they're angular because there is no mechanism on the Moon to make