Extract Contact Model Properties

How can I extract information on the contact model properties in my simulation (e.g., Young's modulus, coefficient of friction, etc.)? For debugging purposes, I want to be able to check that the right contact properties are being applied to different groups of particles and that the coefficient of friction changes when I put in a new 'fix property/global' partway through the simulation. I already know how to extract forces, overlaps, etc. using compute pair/gran/local but this doesn't give me any information on the actual contact model parameters.