The Ultimate Guide to the Terroir of Sancerre, Part 4: Oxfordian Limestone
What is Oxfordian Limestone?
Oxfordian refers to an ancient geological time period. Slightly older and slightly more down-slope than Kimmeridgian, it obviously reflects slightly different tones in its wines. The soil itself is known for being rough and gravel-y. Most Sancerre is grown on Oxfordian limestone though it is often referred to as "Caillottes'' or "Griottes."
How does Oxfordian Limestone affect the wines?
The common thread in all of the top wines derived (at least primarily) from the Oxfordian terroirs is an expressive personality. There’s an emphasis on ripe citrus and crushed stone. There's more immediacy and obvious fruitiness, usually, than the silex-derived Sancerres though they seldom have the tropical ripeness and structural density that the best examples from Kimmeridgian soils often hold.
Generally speaking, these soils produce easy-drinking wines that are intended to be drunk on release. However, I have found that to not always be true, particularly in the case of wines from the venerated commune of Bué.
Where in Sancerre can one find this terroir?
This limestone tends to run north-south from Sainte-Gemme down through Bué and below. This includes wines from, among other places, Verdigny, Sury-en-Vaux, and the center of the Sancerre commune. But it's not that simple, of course. Kimmeridgian soils occasionally pop up here and there, sometimes in conjunction with Oxfordian soils.
What exactly is “Bue”?
The commune of Bué (which includes vineyards surrounding the nearby village of Venoize) is one of the most famous communes of Sancerre, sporting several renowned vineyards such as Chêne Marchand, Grand Chemarin, Petit Chemarin, and Clos de la Poussie. As noted before, the soils are dominated by Oxfordian limestone, but one can also find Kimmeridgian marls, and even silex (flint) popping up in places.
Part of Bué's success is surely derived from several quality domaines making wine here, many of which produce single-vineyard wines. Other cuvées may be labeled according to soil type, such as Jean-Max Roger's cuvée "Les Caillottes." Top names include the aforementioned Roger, as well as Vincent Pinard, Lucien Crochet, and Francois Crochet.
Don't mistake Oxfordian Sancerre's friendliness for simplicity! The wines below, all from Bué, are stunning reference-point Sancerres with complexity and the ability to age.
Who makes these wines?
Many terrific--legendary, even--producers make Sancerre on Oxfordian Limestone. As mentioned before, most Sancerre is on Oxfordian soils. But, it’s impossible to discuss these wines without highlighting the work of Crochet.
In fact, a recent encounter with the 2010 vintage of Lucien Crochet's Sancerre Blanc "Croix du Roy" was one of the most dazzling examples of Sauvignon Blancs I've ever tried, filled with mineral and smoke notes, but also herbs, citrus, and cream. And and it showed no signs of fading – here was a real challenger to 1er cru Chablis, driving home just how much of a crime it is that Sancerre isn't cellared more regularly.
Lucien Crochet, Sancerre "Chene Marchand", 2017
Chene Marchand is probably the Bue’s greatest site, and Lucien Crochet is probably the village’s best producer. Add it up, and this is a must-try for anyone with a passion for top-shelf Sancerre.