This is interesting. Unlike the Italians, the French are very protective of designating their vineyards. The Italians, however, don’t have anything quite like Grand Cru.
means literally ‘great growth’ in French. In Burgundy’s Côte d’Or a grand cru is one of 34 particularly favored vineyards, a decided notch above premier cru. In Alsace, grand cru is a recent, elevated appellation accorded several dozen specific vineyards. In Bordeaux, the words grand cru usually apply to a specific property or château and depend on the region in which it is located.
So what this means is that the Loire Valley is joining the ranks of the elites of Burgundy, Bordeaux and Alsace, where the designation means a lot, including premium pricing.
Most grand crus have specific requirements to earn the name, such as the types of grapes required, the percentages of those grapes, aging requirements, alcohol level requirements and so on.
Quarts de Chaume is a dessert wine made from the signature grape of the Loire Valley, chenin blanc. From Jancis:
extraordinary small enclave within the Coteaux du Layon appellation producing, only in the best vintages and usually only as a result of noble rot infection, sweet white wines from botrytized chenin blanc grapes or, increasingly, such grapes dried on the vine. Total annual production can often be as little as a few thousand cases, from just over 30 ha/74 100 acres of vineyard, supposedly the finest quarter, or quart, of the Chaume part near Rochefort-sur-Loire of Coteaux du Layon. The vineyards here have the advantage of a southerly exposition within a sort of amphitheatre. The brown schist and carboniferous soils are distinctive and result in powerful wines, particularly since the average vine age is high—with a maximum permitted yield of only 22 hl/ha (1.2 tons/acre), which is rarely achieved, few new investments are being made in this minuscule but potentially glorious appellation. The naturally high acidity of the chenin blanc grape endows these wines, very similar to those of nearby Bonnezeaux, with impressive longevity.
Read Decanter’s article about it here.