Inner Core
Possibly solid Fe-Ni · ~1,000 km radius · 5,000+ K
Outer Core
Liquid Fe-Ni · ~3,500 km total radius · No dynamo active
Lower Mantle
Silicate · Perovskite structure · Chondritic composition
Upper Mantle
Olivine → Spinel transitions · No asthenosphere detected
Crust
20–65 km avg · Basaltic/mafic · No plate tectonics — single plate