Gilbert's rocks feature the most prominent of endangered marine wildlife of the North Atlantic: Whales, Bluefin Tuna, Swordfish, Sturgeon, and the Atlantic Salmon.

The rocks on which these mysterious creatures are hand-engraved come from the rugged, wave-battered beaches of North Atlantic and the gravel banks of rushing rivers, hidden deep within the Canadian wilderness. Hand-picked by Gilbert for their individual beauty in shape, form, and colour, these rocks are a pure natural phenomenon, perfect for the art of engraving.

The engraving technique used by Gilbert to achieve this look is similar to the traditional art of "scrimshaw" of the great whaling period, where sailors carved images on white ivory whale teeth and blackened them. Gilbert archived a black patina onto the polished stone. This patina dramatically deepens the colour of the rock. The chisel then creates a fine, white, contrasting line, allowing the images to come to life on the rock surface.