NWA 17708 Howardite Meteorite Slice, 35.21g, Fresh Fusion Crust on 50% Edge

Fresh fusion crust preserved on impact-mixed achondrite

This 35.21g howardite slice from NWA 17708 preserves fresh black fusion crust across approximately 50% of its edge surface. The rippled texture of the crust formed during atmospheric entry as the surface melted and ablated. One face has been sanded to reveal the internal brecciated structure—a mosaic of angular clasts from different source rocks cemented together by impact processes on asteroid 4 Vesta's surface.

The contrasting lithologies visible within the matrix represent fragments of both eucritic basalt and diogenitic orthopyroxenite, the two rock types that dominate Vesta's crust and upper mantle. This mixing occurred during violent collisions that excavated material from different depths and welded it together. The specimen offers a cross-section view: fusion crust on the exterior, fragmented interior structure revealed by cutting.

Structure and features

The sanded face exposes the characteristic brecciated texture that defines howardites. Angular clasts of varying sizes sit suspended in a fine-grained matrix. Some clasts appear darker and more crystalline—likely eucritic material rich in plagioclase and pyroxene. Lighter regions may represent diogenitic fragments dominated by orthopyroxene crystals. The heterogeneous appearance reflects the chaotic mixing process that created this rock.

The fusion crust retains its original black glassy texture with subtle flow lines and ripples. This preservation indicates minimal weathering since the fall. The slice format provides both display value—the contrast between dark crust and lighter interior—and scientific accessibility to the internal structure. Magnetism is very weak to absent, consistent with the non-metallic composition of HED achondrites.

Scientific context

Howardites form exclusively on asteroid 4 Vesta, the second-largest object in the main asteroid belt. Unlike most meteorites, which sample primitive material from the early solar system, howardites represent evolved crustal rocks from a differentiated world. Vesta underwent complete melting and separation into core, mantle, and crust within the first few million years of solar system history. The HED meteorite group—howardites, eucrites, and diogenites—samples this differentiated structure.

Howardites specifically record the impact gardening process on Vesta's surface. Repeated collisions over billions of years excavated material from different crustal depths, mixed it together, and lithified it through shock compression. Each howardite is a unique blend ratio of eucrite and diogenite, making them individually distinct records of Vesta's impact history. NASA's Dawn spacecraft confirmed the Vesta connection through direct surface observations between 2011 and 2012, matching spectral signatures between the asteroid and HED meteorites.

Frequently asked questions

Is this meteorite authenticated? Yes. NWA 17708 is officially classified as a howardite in the Meteoritical Bulletin: NWA 17708. This specimen includes a certificate of authenticity from Treasure Coast Meteorite Co. verifying its classification and origin.

What does brecciated mean? Brecciated texture indicates the rock formed from broken fragments of pre-existing rocks that were cemented together. In howardites, these fragments come from different depths in Vesta's crust—eucritic basalts from the surface and diogenitic orthopyroxenites from deeper layers—mixed by impact events and compressed into a new rock.

What is included with this specimen? You receive the 35.21g NWA 17708 slice, certificate of authenticity, specimen card with classification details, and protective gembox display case.

Why doesn't this meteorite attract a magnet? HED achondrites contain little to no metallic iron, unlike chondrites or iron meteorites. Vesta differentiated early in solar system history, and metal sank to the core. The crustal rocks we sample as HED meteorites consist primarily of silicate minerals—plagioclase feldspar and pyroxene—which are non-magnetic.

Collector significance

This specimen offers collectors direct access to a classified achondrite from a known planetary body at an accessible size and price point. The preserved fusion crust adds display appeal while the sanded interior face provides clear visibility of the brecciated structure. At 35.21g, the slice is substantial enough for detailed examination without requiring specialized equipment.

NWA 17708 was recovered in 2024, making it among the most recently classified Vesta samples available to private collectors. The combination of fresh fusion crust and exposed interior structure makes this slice particularly versatile for both aesthetic display and educational use. Collectors building HED meteorite reference sets will find this howardite complements eucrite and diogenite specimens by demonstrating the impact mixing process that occurred on Vesta's surface. The specimen ships ready for display in its included protective case.

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