The Champenay quarry

The Champenay Quarry extracts and processes in its workshops
exceptionally hard, low porosity quartzitic sandstone. The pink
sandstone of Champenay, exploited for centuries and still referred to
as “Princes' Sandstone”, is the hardest sandstone in Alsace and the
only one that can be polished, contributing to its notoriety among
major contemporary architects.