NWA XXX Ordinary Chondrite Meteorite Individual, unclassified, 820.15g, Flight Oriented with Contraction Cracks

Wedge-shaped atmospheric entry profile

This 820.15g ordinary chondrite individual exhibits pronounced flight orientation visible in its wedge-shaped form and asymmetric fusion crust distribution. The leading surface shows complete ablation features including deep regmaglypts and parallel contraction cracks that formed as the molten crust cooled during atmospheric deceleration. Fusion crust covers approximately 99% of the specimen surface, displaying minimal terrestrial weathering since its recent 2025 recovery in Morocco.

The orientation geometry indicates stable flight through the atmosphere, with the blunt leading edge bearing the majority of thermal stress. This specimen's low magnetic response suggests possible LL group classification, though laboratory analysis would be required for definitive typing. The preserved contraction crack network documents the thermal shock gradient between the superheated surface and cooler interior during the final seconds of atmospheric flight.

Fusion crust preservation and surface features

The fusion crust exhibits exceptional preservation across the entire specimen, showing the glossy black glass coating formed by friction-induced melting during atmospheric entry. Regmaglypts indent the leading surface in parallel rows, marking zones where turbulent air flow stripped away molten material. These thumbprint-like depressions range from shallow curves to deep pockets, documenting the complex aerodynamic forces acting on the meteorite during hypersonic flight.

Contraction cracks radiate across the primary ablation surface in a pattern characteristic of rapid cooling. These fractures developed as the molten fusion crust solidified while the meteorite continued decelerating, creating tensile stress in the cooling glass layer. The crack spacing and orientation provide a record of the thermal gradient and flight attitude during the final phase of atmospheric passage.

Scientific context

Ordinary chondrites represent the most abundant meteorite type recovered on Earth, comprising material from asteroids that never underwent planetary differentiation. These meteorites preserve primitive solar system matter, including chondrules formed in the solar nebula approximately 4.567 billion years ago. The three groups (H, L, LL) differ primarily in their iron content and oxidation state, reflecting formation in distinct regions of the asteroid belt.

Flight-oriented specimens document the physics of atmospheric entry, providing physical evidence of ablation processes, shock heating, and aerodynamic stability during deceleration from cosmic velocities. The preservation of oriented features requires specific flight conditions and mass retention during atmospheric passage. Learn About Meteorites to understand how fusion crust forms and what chondrules reveal about solar system formation.

Frequently asked questions

Is this meteorite authenticated? This specimen is confirmed as an ordinary chondrite based on physical characteristics including fusion crust composition, magnetic properties, and interior texture. While unclassified specimens have not undergone laboratory analysis to determine specific subtype (H, L, or LL) or petrologic grade, authentication as genuine meteoritic material is certain. Each purchase includes a certificate of authenticity documenting the specimen's meteorite classification and provenance.

What does "unclassified" mean for this meteorite? Unclassified indicates that formal laboratory analysis including thin section preparation, electron microprobe analysis, and detailed mineral chemistry has not been completed. Classification requires destructive sampling and significant expense, which many collectors prefer to avoid for display specimens. The meteorite's authenticity is not in question -- only its specific subgroup designation within the ordinary chondrite category.

What causes contraction cracks in fusion crust? Contraction cracks form when the molten fusion crust layer cools and solidifies during atmospheric deceleration. The surface cools faster than the interior, creating tensile stress in the solidifying glass coating. These cracks propagate through the crust in patterns determined by the thermal gradient, flight orientation, and cooling rate during the final seconds of atmospheric passage.

What is included with this specimen? This 820.15g individual meteorite ships with a certificate of authenticity. No display stand is included.

Why does low magnetic response suggest LL classification? Ordinary chondrites are subdivided by total iron content: H (high, 25-31% iron), L (low, 20-25%), and LL (low iron, low metal, 19-22%). Lower metallic iron content produces weaker magnetic attraction. This specimen's reduced magnetic response indicates lower free metal abundance, consistent with L or LL group chemistry, though definitive classification requires laboratory analysis of mineral compositions.

Display value for atmospheric entry documentation

Collectors seeking specimens that document atmospheric entry processes value oriented meteorites for their scientific legibility. This individual preserves the complete sequence of ablation features in their original geometric relationship: leading surface orientation, regmaglypt distribution, and contraction crack patterns. The 820.15g mass provides substantial physical presence while remaining manageable for display and handling.

Recent finds with minimal weathering offer fusion crust preservation superior to historic falls, where decades of terrestrial exposure degrade surface features. This 2025 recovery displays the pristine black glass coating and sharp regmaglypt boundaries characteristic of fresh material. The specimen functions equally well in educational contexts and private collections, providing direct physical evidence of the physics governing meteorite flight and survival through Earth's atmosphere. Explore additional Chondrites to compare fusion crust preservation and orientation features across different fall events and recovery conditions.