Pallasites

Pallasites are a group of stony-iron meteorites composed of a mixture of iron-nickel metal and silicate minerals, most commonly featuring large, transparent to green olivine crystals embedded within a metallic matrix. They are regarded as material from the transition zone between the metallic core and the silicate mantle of differentiated asteroids, where both material types were in direct contact and could coexist under high-temperature conditions during early planetary evolution. In this boundary region, metal and silicate were able to form stable intergrowths, producing distinctive textures that record the physical conditions within an evolving parent body.

The chemical and structural characteristics of pallasites indicate that they formed in a relatively stable environment during the early thermal history of their parent asteroid, before later collisional events disrupted and ultimately destroyed the original body. As a result, fragments from the core–mantle boundary were released into space and later reached Earth as meteorites. These fragments preserve a rare record of the direct spatial association between metallic and silicate material within a single planetary body.