Garden Memorial Stone | Dog Memorials | Grave Marker | Pet Memorial 6-7 Inch. Dog Memorial Stone. Memorialize your dog with their own customized engraved stone pet memorial. This river rock pet memorial stone will range in size of 6-7 inches. I will engrave the name of your pet, a dog bone, and a brief phrase (no longer than 12 characters including spaces). Just leave me the details in the Comments Section during checkout.