The Peak of the Slate Industry in Anjou

The history of the Blue Mine is part of the golden age of slate mining in France and particularly in Anjou. In 1891, the creation of the Angers Slate Commission marked a turning point, bringing together 85% of the national slate production.

Birth and Operation of the Blue Mine

• 1936: Closure following the bankruptcy of the main shareholder, the “Bougère Fils et Pousset” bank of Angers
• 1916: Creation of the public limited company “Ardoisières Angevines de St Blaise”
• 1921: Start of operations
• 1935: Production record with 620 tons of slate, mainly for the British market

The Industrial Revolution of the 19th Century

The 19th century marked a decisive turning point with the introduction of pneumatic machines. This technological advancement allowed miners to reach deeper deposits, up to 126 meters underground, significantly increasing production.

Slate Processing

Once extracted, the slate underwent a transformation process in specialized workshops near the mine. The slate slabs, cut into different sizes, found their use in construction, particularly for roofs, walls, and floors.

The Peak and Decline of the Slate Industry

The slate industry experienced a period of prosperity, contributing significantly to the local economy. However, the decline began gradually, due to the depletion of easily accessible deposits and increasing competition from other building materials.

From Closure to Tourism

1. 1959: Dewatering reveals the good condition of the bottom and the value of the reserves, but economic circumstances prevent reopening
2. 1987/88: Feasibility studies for a tourism conversion
3. 1991: Opening of the Blue Mine as a tourist site, preserving the memory and heritage of the slate industry

Faced with the decline of the industry, a group of enthusiasts undertook to transform the Blue Mine into a museum. This initiative preserves the history and heritage of slate mining in the region, offering visitors a unique dive into the mining past of Loire-Atlantique. The elevator takes visitors directly to 126 meters underground.

This site is the only accessible slate mine in the region, as water is constantly pumped out, unlike other mines which are flooded. This particularity makes it a unique place to explore the rich mining heritage of Anjou.