Molar refractory element (Ca and Al) abundance of planet mantles forming with various devolatilisation trend shapes, given in terms of α and T_D = 10^−β/α, where α and β are defined in Eq. (4). Disk compositions are largely solar, except in C and O abundances, where C/O is varied while preserving ϵ_C and ϵ_O. The devolatilisation trends of Earth (yellow diamond), Mars (red circle), and Vesta (blue square) are indicated. Note that we plot mol% of Ca and Al here, which is limited by the abundance of oxygen that appears together with the refractory elements.