Rafsa 005 Angrite Meteorite Individual, Angrite (plutonic), 2.08g, Coarse Igneous Texture

Coarse-grained plutonic angrite from an ancient differentiated body

This 2.08g individual displays the characteristic coarse-grained texture that defines plutonic angrites, igneous rock that crystallized slowly beneath the surface of a differentiated parent body over 4.5 billion years ago. The visible grain structure reveals a cooling history fundamentally different from the rapidly-cooled volcanic angrites, preserving information about magmatic processes in the early Solar System. Found in Algeria in 2023, Rafsa 005 represents one of fewer than 25 known angrite falls and finds worldwide.

The specimen's size and preservation make it suitable for both display and scientific study. Its classification as a plutonic member of the angrite group places it among the rarest categories of differentiated achondrites, with total known material for all plutonic angrites combined measuring less than a few kilograms globally.

Structure and features

The coarse-grained texture visible in this specimen resulted from slow cooling within the interior of its parent body, allowing large crystals of Al-Ti-rich augite, olivine, and anorthite to form. This contrasts sharply with basaltic angrites, which cooled rapidly at or near the surface and show fine-grained textures. The mineral assemblage reflects crystallization from a calcium-aluminum-rich magma under reducing conditions.

Angrites are characterized by extreme oxygen isotope compositions and old crystallization ages, with some specimens dated to within the first few million years of Solar System history. The plutonic members of this group provide direct evidence of differentiation and magmatic activity on small planetary bodies during the earliest stages of planetary formation.

Scientific context

Angrites formed on a parent body that differentiated early in Solar System history, developing a metallic core, silicate mantle, and basaltic crust within the first 10 million years after CAI formation. The plutonic angrites crystallized from magmas trapped within the mantle or lower crust, while volcanic angrites represent surface flows. The parent body likely experienced catastrophic disruption, scattering fragments that eventually reached Earth as meteorites.

This meteorite type is scientifically significant because it preserves a record of planetary differentiation processes that occurred when the Solar System was less than 10 million years old. Plutonic angrites are particularly valuable for understanding the thermal evolution and magmatic processes of small planetary bodies. Learn About Meteorites to explore how scientists use specimens like this to reconstruct early Solar System history.

Frequently asked questions

Is this meteorite authenticated? Yes. Rafsa 005 is officially classified in the Meteoritical Bulletin as Angrite (plutonic). You can verify this classification through the Meteoritical Bulletin Database. This specimen includes a certificate of authenticity documenting its provenance and classification.

What does plutonic mean in meteorite classification? Plutonic refers to igneous rock that crystallized slowly beneath the surface of a planetary body, forming large mineral grains. This contrasts with volcanic rock, which cooled quickly at the surface and shows fine-grained textures. The coarse grain size in this specimen is direct evidence of subsurface crystallization.

What is included with this specimen? This 2.08g individual comes with a certificate of authenticity and display box. The specimen weight is 2.08g of meteoritic material.

How rare are plutonic angrites? Extremely rare. Angrites as a whole represent less than 0.1% of all classified meteorites, and plutonic angrites comprise only a handful of specimens within that group. Combined total known weight for all plutonic angrites worldwide is less than a few kilograms, making individual specimens highly sought after by collectors and institutions.

Why are angrites scientifically important? Angrites crystallized within the first few million years of Solar System history and preserve isotopic and chemical signatures from that time period. They provide direct evidence of planetary differentiation, core formation, and magmatic processes on small bodies during the earliest stages of planet formation, processes we cannot observe directly today.

Collector significance

Plutonic angrites occupy the apex of achondrite collecting due to their extreme scarcity and scientific importance. With fewer than 25 total angrite specimens known and only a handful classified as plutonic, availability is measured in individual specimens per year globally. This 2.08g individual represents an accessible entry point into one of the rarest meteorite classifications.

The specimen's classification by the Meteoritical Society and its 2023 find date place it among the most recently recognized plutonic angrites. For collectors building comprehensive Angrites collections or institutions seeking representative specimens of early Solar System differentiation, this individual offers documented provenance and scientific value. The combination of size, preservation, and classification makes it suitable for both display and educational applications.

Meteoritical Bulletin entry: Rafsa 005 | Classification: Angrite (plutonic) | Find, Algeria, 2023