As newly formed planets melt, rocky material rises toward the surface, forming a mantle and crust.
Keywords: Astrophysics, Planets--Origin, Rocks, Astrogeology, Planets--Geology
The large crystals in Cumberland Falls formed inside a partially molten aubrite asteroid, while the two black clasts, or fragments, come from a chondritic asteroid that never melted.
The Peña Blanca Springs meteorite belongs to a group, the aubrites, whose chemical composition has led to speculation that they came from the innermost asteroid belt, or possibly even the planet Mercury.
Kenna, a ureilite, comes from an asteroid that did not completely differentiate.
The Johnstown meteorite comes from a large asteroid, probably Vesta, that melted and differentiated.