Katherine Mayline Mason Biltoft passed away peacefully October 13, 2021, at 9:30 p.m. surrounded by her four children, Robert, Trent, Adrian, and Christel.

Mayline was born in El Dorado Arkansas on July 4, 1938, to George Mason, Jr. and Mary Arden Bozemen of Tyler, TX. She had two younger brothers, George III, and James.

Mayline attended Claremont College in California and the University of Alabama, majoring in Geology during the "Sputnik" era, where she took courses in advanced Math and Science. Mayline continued her studies in Oxford, England, where she earned her teaching certification and continued her post-graduate geology work in Vienna, Austria, which sent her to Italy and Mt. Etna in Sicily. She then worked at the United Nations and the Arkansas Geology Society, serving under then-governor Winthrop Rockefeller. Future work and travel opportunities took her to France, Germany, New Orleans, and New York City.

In 1974, the military moved her young family from Oxford, England, to Rapid City, South Dakota, which was home to Mayline for 47 years. According to her, The Black Hills, is among the most interesting geological places on earth.  She often went on trips to the Badlands and the Black Hills, where she enjoyed exploring geological formations and birdwatching. Mayline raised 4 children as a single mother and enjoyed the company of the many wonderful and fascinating people she would call friends and neighbors. She was involved in a variety of groups and causes including the Boy Scouts of America, Audubon Society, KTEQ, Community Theatre, book clubs, bible study groups, and other organizations that the Rapid City community has to offer.

Mayline is survived by her brother, James; four children, 12 grandchildren, and two great-grandchildren.  She was a consummate mother and a devoted grandmother, and instilled in her children the value of education, art, intellectual pursuits, and real-life experiences, as well as respect for the beauty of our natural world. Mayline also valued the promise of youth and engaged with young people whenever possible, often regaling them with stories of her many adventures in the interesting places she lived, leaving everyone she met with a new sense of wonder and possibility.

Always fascinating, always true, and always fearless, Mayline was a wonder and a treasure to all who had the good fortune to spend time with her. She was much loved and will be greatly missed.