Salivary stone. X-ray of a section through the right lower jaw of a 70-year-old patient, showing a very large calculus (stone, oval, white) in the submandibular salivary duct (Wharton duct). Salivary stones (sialolithiasis) are calcified masses that form within a salivary gland or duct. They can cause pain and swelling of the affected area and are usually removed.