Mark Mercer learned the art of thin-section preparation while working at the USGS Laboratories in Denver during his college years (1972-76). Mark received his BS in Geology from Colorado State University in 1976 and spent six years working for Conoco Minerals (Albuquerque) and the US Forest Service (NW Montana). He joined Petrographic Services in Denver in 1983 when it was a subsidiary of Geochem Laboratories (Houston) and later purchased the business in 1986. In 1990 he moved the operation to Montrose where he raised his four children with his wife Pauline.