Ian Mercer worked for the British Geological Survey and Geological Museum for 25 years and was Director of Education for the Gemmological Association of Great Britain for nearly two decades. After working as a geologist in the energy sector, Ros Mercer was a geology and physics teacher for more than 20 years. They have been leaders for the Essex Rock and Mineral Society for many years; UK national advisors for U3A Geology; and officers for GeoEssex – the county geoconservation steering group. In 2020, together they were awarded the Halstead Medal by the Geologists’ Association for their achievements as 'ambassadors in the promotion of geology, contributing to education at all levels'. Ian Mercer is the author of several books on related subjects.