A method and system for assembling building blocks of colloidal particles and also for shaping of colloids for self-assembly for manufacturing, processing and formation of compositions of matter. A first type of particle is selected as a “key” particle constructed to mate with a “lock” particle, the binding arising from depletion forces. A variety of shapes can be used to carry out this method and system to create compositions of matter. Colloids can be shaped by controlled deformation of multiphase colloid particles.