The Diamond M Museum, in Snyder, Scurry County, originated as the private collection of numerous paintings and other art pieces purchased by Claire and Clarence T. McLaughlin over the years. The museum was essentially an outgrowth of their interest in art and their desire to share it with others. Claire McLaughlin in 1921 started collecting music boxes and crystal glasses, among other things. At that time they were not affluent and thus had no thought of assembling a collection, but over the ensuing years it became apparent that their home could not contain the growing number of valuable art treasures. Accordingly in 1949 the McLaughlins established the Diamond M Foundation, using oil royalties gleaned from their Diamond M Ranch properties. The foundation was to offer financial assistance in various charitable and philanthropic activities and later to develop and support a museum to house their collection for viewing by the public.
On April 1, 1964, the Diamond M Museum, housed at McLaughlin's Diamond M Building in Snyder, was formally opened. Some 200 art enthusiasts and civic, business, and education leaders from various West Texas cities were on hand for the opening ceremonies. The guests of honor were artist Peter Hurd and his wife, Henriette Wyeth Hurd. The Lubbock Avalanche-Journal hailed the museum as a cultural landmark that made it easier for people in remote West Texas areas to view prime examples of both eastern and western art. Initially the public exhibition galleries covered only the first floor of the Diamond M Building, but additional galleries were gradually added to the second floor beginning in June 1969. The museum saw a record number of visitors on March 12, 1967, when Peter Hurd's widely publicized portrait of President Lyndon B. Johnson, which Johnson had rejected, was shown just before it was moved to the Smithsonian Institution for permanent display.
The Diamond M Museum collection reflected the varied collecting interests of the McLaughlin family. Over the years they bought paintings by Frederic Remington, Charles M. Russell, W. H. D. Koerner, Peter Hurd, Manuel Acosta, and Frank B. Hoffman. One gallery displayed some seventeen works by N. C. Wyeth, Hurd's father-in-law and one of America's foremost impressionist artists and illustrators. The collection also included an original watercolor, Winter Apples, by Wyeth's son, Andrew. Other art treasures in the collection included prints by Currier & Ives, bronze sculptures by George Phippen, Charles M. Russell, Frederic Remington, and James Earle Fraser, carved ivory and jade, and soapstone pieces created by Eskimo artists in Canada. The museum also had changing exhibits by contemporary artists. During the 1960s McLaughlin often gave rising young artists opportunities to show at the museum and also bought works from them.
After the death of Claire McLaughlin in 1971 and that of her husband four years later, the foundation's responsibilities were carried on by its board of trustees which included the McLaughlin heirs. In 1981 a contract was drawn up with Western Texas College to administer the museum through the Scurry County Museum with funds provided by the foundation, which also continued to acquire art. The contract included provisions for professional staffing of the museum, which spurred a higher number of changing exhibitions. These temporary exhibitions, some organized by the staff and others borrowed from outside institutions, used themes reflecting the variety of the museum's collections and, along with the permanent exhibitions, provided opportunities for increased public education programs. In 1983 the museum initiated traveling exhibitions of its own works and circulated them to other museums and galleries throughout Texas. In 1992 the Diamond M Museum closed, and the collection was given to the Texas Tech Museum in Lubbock.