François Cotat Sancerre Les Monts Damnés 2013
After my return from Bordeaux I have spent the weekend reading up on the limestones of the Central Loire. I am conscious that the development of my Loire Valley wine guide has been on hold for a little while, simply because I have been just too busy to get around to it. I am also dithering as to which region I should begin with. I am drawn to Muscadet, but during the weekend I landed in Sancerre, principally because of this bottle I guess. I am sure most wine drinkers already know of Kimmeridgian limestone and its relevance to wine, although I suspect this is in many cases through reading around the wines of Chablis rather than Sancerre. That Kimmeridgian limestone is generally seen as superior to Oxfordian (older) and Portlandian (younger) limestone is probably also old news.
The Kimmeridgian age began 157.3 million years ago; curiously, although it is the Cretaceous period that is perhaps most associated with the laying down of limestone, creta being Latin for chalk, both the Oxfordian and Kimmeridgian ages are in the Upper Jurassic. The beginning of the Kimmeridgian is marked by the appearance of Pictonia baylei, a species of ammonite, in the fossil record, while the end-point seems to have shifted around in recent years, but geologists seem to have settled on 150.8 million years ago. The Bureau de Recherches Géologiques et Minières (BRGM), an organisation charged with the geological mapping of France, have identified at least three types of Kimmeridgian stone running up Les Monts Damnés, the famous vine-jeweled mountain which towers over the village of Chavignol.
On the lower parts of the slope there is Calcaire de Buzançais, which is named for a town in the Indre département, southeast of Tours. This is Lower Kimmeridgian limestone, typically rich in fossils, although geologists distinguish it as much for the absence of ammonites as the presence of any other. Walking up the slope, we come to another classic type, the Marnes de Saint Doulchard, a marlstone which straddles the boundary between the Lower and Upper Kimmeridgian. This is named for a commune in the Cher département, on the outskirts of Bourges, and by contrast with the lower limestone this one is rich in fossilised ammonites.
While the Buzançais and Saint Doulchard stones are perhaps the two best known Kimmeridgian limestones in this region, responsible for the classic terres blanches soils, further up the slopes there are more layers of fossil-rich Kimmeridgian stone. This is Marnes et Lumachelles à Exogyra virgula, a mix of marlstone with conglomerated fossils (a lumachelle) dominated by Exogyra, a comma-shaped fossilised oyster which typifies Kimmeridgian stone. Curiously, the BRGM maps also have here a layer of Calcaire à Astartes, a stone rich in bivalve molluscs, ascribed to the Kimmeridgian, although I think this may be an error, as most geologists have this down as Oxfordian (any wine-interested geologists please feel free to correct me on this).
Why, though, does all this matter? Why has Kimmeridgian limestone gained such significance when it comes to wine? That these rocks and overlying soils give wines of high quality is clear, in Sancerre and in Chablis, as vignerons have recognised this for centuries. When asking exactly why, however, there are numerous theories. It may be related to the acidity in the overlying soils, which may be ameliorated by levels of calcium in the rock. As the rocks weather, the calcium from ancient fossils leaches into the soil, lowering the acidity. As Kimmeridgian rocks seem to have fewer fossils than Portlandian rocks, leading to more acid soils, this may be important. In addition, the differing abilities of the rocks to retain water may be significant, as the Kimmeridgian marls may be better at this than harder, purer Portlandian limestones.
This is something I will continue to investigate for my Loire Valley guides, but for now it s time to pull a cork (phew). From one of the greats of the Sancerre appellation, the 2013 Les Monts Damnés from François Cotat proves that, no matter how much we discuss terroir (and I certainly believe terroir is important) wine is ultimately made by man or woman, and the skill and methods of that individual clearly also have a profound effect on the finished wine. Few in the region make wines that age so convincingly as those of François Cotat (although there are certainly others that do, and some are quite under-appreciated in my opinion). In the glass this very young wine has a pale hue, with a bare tinge of green. The nose opens out to reveal apple, iced mint, rosemary and sage, the style quite full and savoury. The palate is hugely impressive, with more mint ice and a bitter grapefruit substance, with green apple and pear skin. A very succulent style despite this challenging character, supple, bright with lovely acidity and a gentle, pithy substance. As it opens in the glass, it also reveals richer hints of acacia and elderflower. An attractive wine, from fine Kimmeridgian terroir and a dedicated vigneron, and I see no reason why it shouldn’t age as well as many other vintages from this cellar, with ten, fifteen or maybe even twenty years ahead of it. 17.5/20 (5/12/16)