modelling properties of alloys

Dear hive mind, I seem to be having a creativity drought today. Can any of you lovely people suggest an alternative to the RSC plasticine+sand method for modelling how an alloy has different properties to its component elements? We don't want to make solder for real and don't have the plasticine to spare for ditching after use (covid rules). I tried cornflour-paste +/- sand, to see if it affected properties (e.g. speed with which a 10g mass sank into it), but this did not give me enough of a difference to be convincing.
try different coloured paints, ie red + yellow = orange
blue and yellow = green and so on. the different paints are the different elements and the resulting colour the alloy


Don't lick, smell or touch it and you won't die.
Could compare coin alloys to their standard metal properties, like copper malleability to bronze.