A method of marking an object for identification purposes uses a local heating source, preferably a solid-state or fiber laser, to form a multi-symbol encoded encrypted monochrome or polychrome message with identification parameters of the object by impacting its surface. The message is created by modifying optical properties and structural configuration of the surface to create contrast microscopic imprints comprising cluster nanostructures of elements of the material of the surface. Encoding the message is based on a primary code array of correspondence of each of the message symbols to a multibit combination of 0 and 1 respectively representing absence and presence of the heating source impact imprint. Encrypting is effected by creating particular code arrays based on the primary one by means of random perturbation of its components. The invention makes it practically impossible to counterfeit the objects, replace them, or make a subject of others illegal actions.