Because New Mexico Institute of Mining and Technology is a mining college, silver and gold are obvious choices for school colors, but it is not currently known how or when they were chosen.
The Intercollegiate Bureau of Academic Costume (IBAC) probably assigned New Mexico Institute of Mining and Technology a hood lining in the late 1940s or 1950s. A list compiled by Kevin Sheard in Academic Heraldry in America (1962) described the institute’s hood lining as silver with a gold chevron. Identical descriptions were also cited in IBAC lists from 1969 and 1972.