Once considered an abundant and nearly infinite resource, sand is today at the heart of major challenges linked to urbanisation and environmental transformation. Used in construction, industry, and infrastructure, it is one of the most consumed raw materials in the world after water.

This lecture aims to explain why this seemingly ordinary resource has become strategic. It addresses extraction dynamics, ecological impacts on coastlines and rivers, as well as the economic and geopolitical tensions it generates.

By putting these issues into perspective, the talk invites us to rethink our relationship with the materials that shape our infrastructures and contemporary landscapes.

Stéphanie Girardclos is a lecturer and researcher at the University of Geneva, where she teaches environmental geology and geomorphology. A specialist in lacustrine sedimentology, she leads research on the interaction between geological processes and human society, using sediments as archives of past environments.