The Blue Stones of Saint Leonard des Bois Low-poly 3D model

The Activities of Men: The Waste of Forge Work

The iron-rich soil of Saint-Léonard-des-Bois, located in the Alpes Mancelles region of France, has historically attracted numerous ironworking activities. The town became renowned for its expertise in processing this valuable ore. Many workshops were established along the Sarthe River to harness the river's water power for their forges.

Today, remnants of these once-thriving workshops can still be found in the form of slags, commonly referred to as the blue stones of Saint-Léonard. These stones are a testament to the industrious past of the region and the ironworking skills of its inhabitants. The unique blue hue of these stones results from their composition as metallurgical slag, a byproduct of the iron smelting process. This slag, known as clinker, is an alumino-silicate calcium glass formed during the smelting process, and its blue color is attributed to the Tyndall effect, where tiny particles within the glass scatter blue light.

These blue stones, with their sharp, glass-like fractures and fine grain, serve as a historical marker, reminding us of the town's significant contribution to the ironworking industry in France. The black stones, also found in the region, with their high iron content and magnetic properties, further emphasize the area's rich metallurgical heritage.