There are many techniques for carving stone or etching images into a stone surface.  Here are four of the most popular processes.

Bas Relief - The entire surface of the monument is cut away, leaving the flowers in bas relief on top of the other surface.

Etching - Typically used on black granite, this technique cracks the surface of the granite using a diamond-tipped tool or a laser.  When the granite's polished surface is etched it creates a high contrast image on the stone.  This is popular for photos and portraits.

Flat Carving or Line Carving - This process involves sandblasting an image (of a flower, for example) on the stone.  There is no dimensioning or relief given to the carving.

Shaped Carving - This is a time-consuming technique that requires years of training with sandblast tools.  This process involves shaping the petals and leaves of flowers with a special sandblast nozzle.  Shaped carving gives depth and a sense of reality to the carvings on a monument.