An aerosol-forming substrate comprises a first material and a second material, the first material being comprised in the aerosol-forming substrate as a first plurality of discrete elements and the second material being comprised in the aerosol-forming substrate as a second plurality of discrete elements. The first material comprises an aerosol-former and has a first thermal conductivity, and the second material has a second thermal conductivity that is greater than the first thermal conductivity. The presence of the discrete elements of the second material in the aerosol-forming substrate produces a substrate with augmented thermal conductivity resulting in improvements in aerosol generation and delivery.