A meteorite thin section from The Curchin Collection
What is NWA 7034?
The NWA 7034 Martian meteorite was purchased in Morocco in 2011. Since then, multiple fragments of similar composition have been found in Rio de Oro, Western Sahara. NWA 7034 is nicknamed “Black Beauty” because of its well developed black fusion crust from entering earth’s atmosphere.
So what’s so special about NWA 7034? First off, it doesn’t fit within the three known types of Martian SNC meteorites: shergottite, nakhlite and chassignites. NWA 7034 is a polymict regolith breccia. Let’s define that:
polymict⇒ consists of multiple fragments of different rock types (including mineral fragments, impact melt, basalt and other lithic clasts)
regolith⇒ loose layer of materials found over hard bedrock – can include dust, soil and broken rock.
breccia⇒ a rock composed of rock fragments cemented together
Research has shown that the composition of NWA 7034 best represents the analyzed martian crust that rovers have sampled. Additionally there’s up to 10 times more water in this meteorite than the other SNC meteorites. To top it all off, zircons in the fragments have dated the meteorite as the oldest Martian meteorite, >4.3 billion years old. For all these reasons and more, NWA 7034 is worth ~$10,000 per gram!
Under the Microscope
In transmitted, cross-polarized light, NWA 7034 shows off the different rock fragments and individual phenocrysts of plagioclase and pyroxene which are all set within a dark fine-grained groundmass. The “Black Beauty” nickname holds true under the microscope!