The mineral rectorite is the regularly interstratified sequence of illite- and smectite-like layers with a ratio of 1:1 and a Reichweite (R) ordering parameter R1. The illite- and smectite-like ...

The cave of the Grotte des Fées at Châtelperron lies in the small valley of the Graveron, between the larger valleys of the Loire and the Allier, on the northern flanks of the Massif Central ...