The microphotographs show a tungsten carbide coating on the diamond grain. This coating protects it against graphitization at elevated temperatures (for example, during operation of the diamond cutting tool). The coating was formed spontaneously by the mechanism of gas transport reactions during sintering of diamond with Fe-Cu-Co-Ni matrix. These SEM images resemble not only the mosaic technique of Gustav Klimt, but also form an association with the plot of the "The Kiss" painting, in which a man gently embraces a woman, hiding her from the outside world.