SAPPHIRE California walnut inshell refers to walnuts that are grown in the state of California and are sold in their natural protective shell. These walnuts typically have a light brown or tan shell, which encases the nutmeat inside. The nutmeat itself is characterized by a mild, buttery flavor and a slightly crunchy texture. California walnuts, both inshell and shelled, are known for their nutritional benefits, including being a good source of omega-3 fatty acids, antioxidants, and various essential nutrients.