January 3, 1944 – January 23, 2025

James “Jim” Calvin died January 23, 2025, at St. Anthony’s Hospital in Lakewood, Colorado. Jim was born on January 3, 1944, in Chicago, Illinois. An only child, Jim was a rascal in his youth who found adventure at each and every opportunity.
Before landing in Colorado to attend the Colorado School of Mines, Jim grew up in Dayton, OH, Jackson, MI, and Houston, TX. It was in Houston that Jim was introduced to the oil fields, the first love of his life. Once at Colorado School of Mines he was a was a proud SAE fraternity brother. He received a professional degree as a petroleum engineer in 1972. Jim spent the next 34 years working for Amoco in petroleum; in the fields, the office, and in research both domestically and internationally.
Jim met Barbara Mathews on a blind date on August 29, 1969 and exactly one year later she officially joined his adventures. Together they raised 2 children and have enjoyed their 5 grandchildren. Their greatest love has been time with family and friends, especially while traveling the world.
Jim retired from Amoco in 1998 and joined Nations Energy. He was incredibly proud of his work with the company and in his role as Chief Operating Officer he was able to help the company build orphanages, support hospitals, build a technopark, and greatly impact communities in Kazakhstan and Azerbaijan. He then retired from Nations in 2007 to take on the new role of proud Papa.
Jim always loved the Colorado mountains and was at his happiest when in them. He traveled the world visiting 115 countries and lived in 4; but Colorado was always home. He would belt out John Denver’s “Rocky Mountain High” or “I Guess He’d Rather Be in Colorado” with a great big smile on his face.
We will remember Jim wearing his Broncos shirt (always with a pocket on the front for his “stuff”) and with a Coke Zero in hand. He never missed a Broncos game and was a proud season ticket holder.
Jim was welcoming to all. He enjoyed having a house full of people for any event; he will be remembered for his warmth, kindness, and most of all for his generosity. He will also be remembered for liking to do things his own way, ignoring advice from others, and smiling all the while.
Many National Repertory Orchestra musicians have been welcomed by Jim and Barbara over the last 20 years. Nothing made Jim happier than a house and hot tub full of their “kids.”
Of all his achievements, Jim was the proudest of his family. Daughter Ashley and son-in-law Timothy live in Madison, AL with their 3 children: Rory (17), Owen (17), and Holland (15). He was having fun watching the college hunt for the oldest two and loved to hear about each of the kids’ adventures and accomplishments in sports and school. Son Mathew and daughter-in-law Lonnae live in Okinawa, Japan, with their 2 children: Penelope(11) and Christopher(8). Jim loved to visit them and was astounded by their massive Thanksgiving celebrations.
Jim was pre-deceased by son Christropher Calvin, and has quietly supported an arts scholarship at The University of Northern Colorado in Christopher’s name.