NWA 17708 Howardite Meteorite Part Slice, 21.31g, 50% Fresh Fusion Crust

Fresh fusion crust preserves half the edge of this Vesta fragment

This 21.31g part slice of NWA 17708 displays approximately 50% coverage of fresh, rippled fusion crust along its edge surfaces. One face shows sanded texture revealing the internal brecciated structure, while the natural exterior preserves the thermal scarring from atmospheric entry. The specimen form factor balances structural detail with display presence.

Howardites represent surface regolith from asteroid 4 Vesta, formed through impact gardening that physically mixed eucritic basalts with deeper diogenitic orthopyroxenites. This specimen exhibits visible lithic clasts of contrasting composition embedded in a fine-grained matrix. The fusion crust retention on a part slice is notable, as most cutting operations remove atmospheric ablation features entirely.

Brecciation and lithic heterogeneity

The sanded face reveals polymict texture characteristic of regolith breccias. Light and dark clasts ranging from submillimeter to several millimeters appear throughout the matrix, representing fragments of both eucritic and diogenitic parent lithologies. These angular to subangular fragments show sharp boundaries against the finer groundmass.

The preserved fusion crust displays rippled flow textures formed during hypersonic atmospheric passage. This thin glassy rind marks the original exterior surface of the meteoroid before terrestrial recovery. Fusion crust on achondrites typically appears darker and more vitreous than on chondrites due to the crystalline nature of the pre-entry rock.

Scientific context

NWA 17708 belongs to the howardite-eucrite-diogenite (HED) clan, a suite of achondrites linked to asteroid 4 Vesta through spectroscopic matching and data from NASA's Dawn mission. Howardites specifically sample Vesta's impact-processed regolith rather than coherent crustal or mantle units. Impact events on Vesta's surface excavated both basaltic eucrites from the crust and orthopyroxene-rich diogenites from deeper layers, mixing them mechanically into breccias.

Vesta differentiated early in solar system history, developing a metallic core, ultramafic mantle, and basaltic crust within the first few million years after CAI formation. Howardites preserve a record of this differentiation through their mixed composition, and they document the intense collisional environment of the main asteroid belt. Learn more about meteorite classification and planetary science at Learn About Meteorites.

Frequently asked questions

Is this meteorite authenticated? Yes. NWA 17708 is classified as a howardite in the Meteoritical Bulletin Database. You can verify this classification at Meteoritical Bulletin: NWA 17708. This specimen includes a certificate of authenticity from Treasure Coast Meteorite Co.

What does howardite mean? Howardites are polymict breccias containing fragments of both eucrite (basaltic) and diogenite (orthopyroxenitic) lithologies. They represent regolith from asteroid Vesta's surface, mechanically mixed by impact cratering rather than formed through igneous processes.

Why does this achondrite have such weak magnetism? HED achondrites crystallized from differentiated magma on Vesta and contain minimal metallic iron-nickel. Unlike chondrites, which preserve metal grains from the solar nebula, differentiated asteroids sequestered their metal into cores. The silicate minerals in howardites are essentially non-magnetic.

What is included with this specimen? This listing includes the 21.31g NWA 17708 part slice, certificate of authenticity, custom specimen card with classification details, and protective gembox display case.

Why collectors value howardites

Howardites occupy a select position in collections due to their confirmed asteroidal origin and their representation of surface processes on a differentiated body. While eucrites and diogenites sample Vesta's interior structure, howardites capture the dynamic surface environment shaped by billions of years of impacts. The preservation of fusion crust on this part slice adds terrestrial fall context to the specimen's asteroidal history.

At 21.31g, this piece offers substantial hand presence while remaining accessible for focused HED collections. The mixed lithology visible in the sanded face provides educational value for understanding impact mixing and regolith formation on airless bodies. Collectors building comprehensive HED Meteorites suites or Howardites specifically will find this recently classified material represents 2024 recovery efforts in Mali.

Meteoritical Bulletin entry: NWA 17708 | Classification: Howardite | Find, Mali, 2024