Gneiss and Orthogneiss
In reality, of course, there is more to Anjou than schist – quite a lot more in fact – and some of the most highly regarded sites in Sancerre have soils of flint rather than limestone caillottes, griottes or marnes blanches. And, similarly, there is more to Muscadet than gneiss and its friend, orthogneiss, with many of the region’s most admired wines coming from the three other terroirs which I have already explored in this guide, namely schist, granite and gabbro.
Nevertheless, while it undeniably has some competition for the crown, gneiss is arguably the mother rock for the Muscadet vineyard. There is a large batholith of gneiss running beneath the Sèvre and the Maine, as well as the communes of Saint-Fiacre and Monnières which lie between the two rivers, and gneiss therefore underpins the very heart of the Muscadet Sèvre et Maine appellation. Gneiss also reaches out to touch numerous other communes and vineyards, stretching northwards beneath the commune of La Haye-Fouassière, wrapping itself around the Marais de Goulaine. Even the Butte de Goulaine, the long and low-lying hill famed for its distinctive soils of amphibolite and serpentinite, actually has a backbone of gneiss.
Gneiss, it seems, is everywhere, but it is around Saint-Fiacre and Monnières that it perhaps reaches its apogee, from lieux-dits such as Les Gras Moutons. These are the soils that gave Louis Métaireau, once one of the region’s most renowned vignerons, some of his greatest wines including Premier Jour in the 1989 vintage, securing a place for gneiss in the hearts of all committed Muscadet drinkers. And it is where Vincent Caillé (pictured above), makes various cuvées of gneiss, not least the Terre de Gneiss cuvée, a joint project with Christelle Guibert. But before we come to the wines, let us first turn our attention to gneiss itself, its origins and its characteristics. In doing so we will answer this rather obvious question; if gneiss is so important, why do I only come to it now, after dealing with the region’s other principal metamorphic rock, schist?