Erg Chech 002 Ungrouped Achondrite Meteorite Individual, Achondrite-ung, 0.80g, Andesitic Crust Fragment

A fragment of the oldest volcanic crust

This 0.80g individual preserves the andesitic composition that distinguishes Erg Chech 002 from all other achondrites in world collections. The specimen displays noticeable reddish-brown terrestrial staining across portions of the surface and interior matrix, consistent with the Saharan Desert environment where this meteorite was recovered in 2020. The Meteoritical Bulletin reports minor goethite as a secondary weathering product in EC 002 specimens, a direct result of groundwater interaction in the find location.

The surface shows the characteristic gray-green matrix typical of this meteorite's pyroxene-plagioclase assemblage, with staining concentrated in fractures and exposed interior surfaces. This individual retains its natural exterior geometry from the breakup of the parent mass during atmospheric entry or ground impact.

Andesitic mineralogy and texture

Erg Chech 002 consists predominantly of plagioclase feldspar and pyroxene crystals in proportions that match terrestrial andesite, a volcanic rock type commonly found in subduction zones on Earth. This mineralogy requires formation through partial melting and fractional crystallization in a silica-rich magma system, processes that occurred on a differentiated protoplanet with a defined crust-mantle boundary.

The fine-grained texture indicates rapid cooling at or near the surface of its parent body, consistent with extrusive volcanism. This specimen preserves that crystallization history in a hand-sized fragment representing crustal geology from the first few million years of solar system formation.

Scientific context

Erg Chech 002 crystallized approximately 4.565 billion years ago, making it older than any other volcanic rock yet analyzed. This age predates the formation of Earth's crust by tens of millions of years. The meteorite formed on a protoplanet that achieved full differentiation into core, mantle, and crust before catastrophic disruption during the early bombardment phase of solar system evolution. No parent body has been identified; the protoplanet that produced this crust no longer exists as an intact object.

The andesitic composition indicates a complex magmatic evolution rare among differentiated asteroids, most of which produced basaltic or ultramafic crustal rocks. Erg Chech 002 demonstrates that protoplanetary volcanism in the early solar system was more geologically diverse than the surviving asteroid belt suggests. Collectors seeking specimens that document primordial planetary processes will find few examples with greater scientific significance. For comprehensive context on meteorite classification systems and formation mechanisms, see Learn About Meteorites.

Frequently asked questions

Is this meteorite authenticated? Erg Chech 002 is classified in the Meteoritical Bulletin as an ungrouped achondrite. Meteoritical Bulletin entry: Erg Chech 002. This specimen includes a certificate of authenticity documenting its classification and provenance.

What does the reddish-brown staining indicate? The staining results from terrestrial weathering in the Algerian Sahara, where groundwater introduced iron-bearing minerals into fractures and porous regions of the meteorite. The Meteoritical Bulletin identifies goethite as a weathering product in EC 002 specimens. This staining does not affect the specimen's scientific integrity or primary mineralogy.

What is included with this specimen? This listing includes the 0.80g individual meteorite and a certificate of authenticity. No display stand is included.

What does "ungrouped achondrite" mean? Ungrouped achondrites do not fit into established meteorite groups based on mineralogy, oxygen isotopes, or chemistry. Erg Chech 002's andesitic composition and ancient age distinguish it from HED meteorites, lunar samples, Martian meteorites, and all other classified achondrite groups, placing it in its own category.

Why is the age of this meteorite significant? At 4.565 billion years, Erg Chech 002 crystallized within the first few million years of the solar system's existence, before most planetary bodies had completed differentiation. It represents a snapshot of crustal geology from a time period for which no other volcanic samples are available, making it the oldest known piece of planetary crust.

Collector significance

Erg Chech 002 stands alone among meteorites for its combination of extreme age, andesitic composition, and protoplanetary origin. No other specimen type in private hands represents volcanic crust from the first epoch of planetary formation. The 2020 recognition of this meteorite expanded the known diversity of early solar system geology and provided the first andesitic sample from beyond Earth.

This 0.80g individual offers an accessible entry point into one of the most scientifically important meteorite finds of the 21st century. The visible weathering staining provides a documentary record of the specimen's terrestrial residence time while preserving the primary igneous texture beneath. For collectors building representative suites of achondrite types, Erg Chech 002 fills a category no other meteorite can occupy. Additional ungrouped achondrite specimens and related differentiated meteorite types are available in the Ungrouped Achondrites collection.

Meteoritical Bulletin entry: Erg Chech 002 | Classification: Achondrite-ung | Find, Algeria, 2020