.40" Carbonaceous Chondrite Meteorite Fragment (.48 g) - NWA 12925

NWA 12925 was discovered in 2018 and purchased in December 2018 by Dustin Dickens in Morocco from an anonymous dealer. It's classified as a carbonaceous chondrite (CK5) and its physical characteristics consist of a dark, fusion crusted exterior. Cut and broken surfaces reveal a dark gray interior, some scattered CAIs visible and a few chondrules over 1mm. The total known mass of NWA 12925 is 3.8 kg.

Meteoritical Bulletin: Entry for The NWA 12925 Meteorite

About Chondrites

A chondrite is a stony (non-metallic) meteorite that has not been modified by either melting or differentiation of the parent body. Chondrites are formed when various types of dust and small grains in the early Solar System accreted to form primitive asteroids. Some such bodies are captured in the planet’s gravity well and pulled to the surface. They are by far the most common type of meteorite, representing about 86 percent of all meteorites that have fallen to Earth.

Prominent among the components present in chondrites are the enigmatic chondrules, millimeter-sized spherical objects that originated as freely floating, molten or partially molten droplets in space; most chondrules are rich in the silicate minerals olivine and pyroxene. Chondrites also contain particles of various metals such as nickel, iron, and aluminum. These formed at the very beginning of the solar system and aggregated over time: they are the oldest rocks known on Earth!

Chondrites are divided into about fifteen distinct groups on the basis of their mineralogy, bulk chemical composition, and oxygen isotope compositions. The various chondrite groups likely originated on separate asteroids or groups of related asteroids. Each chondrite group has a distinctive mixture of chondrules, refractory inclusions, matrix (dust), characteristic chondrule sizes, and other components. Other ways of classifying chondrites include weathering and shock. The L chondrite group is the most common of these.