LUN - Mare Basalts
The members of this group are mare basalts, consisting of phenocrysts
of olivine and augite, set within a fine-grained matrix of plagioclase and
pyroxene. The accessory minerals include chromite, ilmenite, apatite,
troilite, and minor nickel-iron metal. Lunar mare basalts are much younger
than the anorthositic highland rocks. They were formed during volcanic
eruptions within large basins, mostly located on the near side of the Moon,
their shapes delineating the imaginary face of the "Man in the Moon".
Large portions of this pristine basaltic crust have been transformed into
a regolith by ongoing meteorite bombardment. Consequently, most LUN B
members are mare basalt regolith breccias, e.g., the Antarctic lunaites
Yamato 793274, Yamato 981031, and QUE 94281. Similarly, most other mare
basalts are also heavily brecciated, containing notable regolith portions.
Still, there is one unbrecciated member known - the pristine mare basalt
NWA 032, and its pairing NWA 479. The latter meteorite was recovered by
our team near Khter n'Ait Khebbach, Morocco, in November 2000, and is one
of our most unusual finds. Recent research suggests that this unique mare
basalt crystallized just 2.8 billion years ago, providing evidence for a
prolonged lunar volcanism and making this one of the youngest lunar
basalts analyzed so far.
NWA 032
Lunar olivine-pyroxene basalt
Found october 1999, Morocco
TKW : 300 gr
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NWA 32 - 01
5.737 gr
Very nice triangular endcut!
Price
on request
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NWA 32 - 02
1.632 gr
Very thin and superb slice !
SOLD
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NWA 32 - 03
1.247 gr
Nice slice with crust on the edge
SOLD
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NWA 32 - 04
0.497 gr
Very nice and thin slice with crust
SOLD
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NWA 32 - 05
0.464 gr
Very nice and thin slice of Lunar meteorite !
SOLD
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NWA 32 - 06
2.54 gr
Very nice and thin slice with crust
two large glass melt pockets !!
SOLD
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NWA 32 - 07
1.463 gr
Very nice and thin slice with crust
two large glass melt pockets !!
SOLD
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LUN Group - Lunar Meteorites
The LUN group is a most intriguing class of achondrites since its members
represent different types of lunar rocks, i.e., genuine pieces of the Moon.
Scientists have speculated for centuries about the possibility that some of the
meteorites in our collections might actually be of lunar origin, and some
researchers even believed the enigmatic tektites were the products of major
volcanic eruptions on the Moon. Finally, with the return of lunar samples by the
Apollo and Luna missions in the 1960's and 1970's, it was thought that a
definitive test for these ideas was now available. However, subsequent
comparisons yielded no match to either tektites or any group of achondrites, and
it would take an additional decade before the first lunar meteorite would be
identified.
In the late 1970's, Japanese and American researchers recognized the ice
fields of Antarctica as a promising hunting ground for meteorites, with the
subsequent recovery of thousands of new meteorites; among these, several lunar
meteorites, or "lunaites", have been identified. These are mostly
small stones resembling certain samples returned by the Apollo missions. In
1990, a small stone weighing just 19 grams was found in Calcalong Creek,
Australia. It was thereafter recognized as the first non-Antarctic lunaite.
During the past four years, professional meteorite hunters have recovered
several more lunaites from the hot deserts of Africa and Oman. Today, the LUN
group comprises about 25 members, excluding all probable pairings, with a total
known weight of about 8.5 kg (have a look at our list
of lunar meteorites).
Lunar meteorites are of major scientific importance because they probably
originate from areas of the Moon that were not sampled by the Apollo or Luna
missions. Most lunaites in our collections obviously have been blasted from the
lunar highlands that cover the far side of the Moon. Only a few lunar meteorites
have their origin from the smooth lowlands, the maria of the near side, which
served as the preferred landing sites for the Apollo missions. Four different
types of lunar rocks have been sampled in the form of meteorites thus far:
anorthositic highland rocks (LUN A), mare basalts (LUN B), mare gabbros (LUN G),
and a unique lunar norite (LUN N), representing the deep, olivine-rich layers of
the lunar crust. All of these meteorites share the typical features of lunar
rocks, e.g., similar manganese to iron ratios, and oxygen isotopic compositions
that plot on the terrestrial fractionation line. We will discuss each group of
lunar meteorites below.
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