Selected minerals from the Nord to discover the mineralogy and mineral species of this department, specimens are for sale. Calcite crystals from Glageon, Haut-Lieu, near Avesnes-sur-Helpe, or Limont-Fontaine, baryte and fluorite from Wallers-en-Fagne (formerly Wallers-Trélon), gypsum from Leforest, siderite and quartz from Valenciennes coal mines, etc.