Diogenite Meteorites Asteroid 4 Vesta Specimen NMW 7831 Western Sahara Display

Location: Western Sahara

Weight: 0.4 Ounces (Display)

Dimensions: 2.3 Inches Long, 1.5 Inches Wide, 0.6 Inches Thick (Display)

Comes with a Free Display Case.

The item pictured is the one you will receive. 

Diogenite is a type of meteorite classified within the group of achondrites, which are stony meteorites that have undergone differentiation and crystallization processes similar to those that occur in planetary bodies. Specifically, diogenites are believed to originate from the asteroid 4 Vesta, one of the largest bodies in the asteroid belt. This classification is part of a broader understanding of meteorites and their origins, which provides insights into the early solar system's formation and evolution.

Diogenites are dominated by orthopyroxene, an iron- and magnesium-rich silicate mineral that accounts for their typically dark coloration and relatively high density. Alongside orthopyroxene, many specimens contain varying amounts of olivine, plagioclase feldspar, and minor metallic phases. These mineral proportions differ from one diogenite to another, recording subtle variations in crystallization conditions and parent-body evolution.

Texturally, diogenites are notable for their coarse-grained crystalline fabric, indicating formation in a slowly cooling environment beneath the surface of their parent body. The prolonged cooling allowed large crystals to grow, in contrast to the fine-grained textures seen in rapidly erupted volcanic rocks. Numerous diogenites exhibit cumulate textures, produced when early-forming, dense crystals settled within magma chambers as molten material differentiated over time.

Their origin is closely tied to the internal evolution of the asteroid 4 Vesta. During Vesta’s early history, partial melting produced basaltic magmas that separated into distinct layers. As these magmas cooled, minerals such as orthopyroxene crystallized early and settled downward within subsurface magma chambers. Subsequent impact events excavated this deep-seated material, ejecting fragments into space that eventually reached Earth as meteorites.

Diogenites offer critical insight into planetary differentiation, the process by which rocky bodies separate into chemically and mineralogically distinct layers. By studying their mineralogy and textures, scientists gain a clearer picture of thermal conditions and magmatic activity in the early solar system.

Within meteorite classification, diogenites form part of the HED group—Howardites, Eucrites, and Diogenites. Howardites are brecciated mixtures of eucritic and diogenitic material, while eucrites represent basaltic crustal rocks from the same parent body. Together, these meteorites provide a detailed record of Vesta’s geological evolution and serve as a model for understanding differentiation on small planetary bodies.