Terroir of Tokaj
The diversity of Tokaj wines is rooted in the region’s soil. The earth here is rich in various minerals, which, in turn, imparts Tokaj wines with their particular aromas.
Middle and Upper Miocene volcanic activities created a significant diversity of rocks and volcanic formations on Tokaj’s slopes. Essentially, the full suite of volcanic rock types is found in Tokaj, including rhyolite, rhyodacite, dacite, and andesite. These rocks are distinguished by their silica [SiO2] content and combine with other volcanic detritus to form Tokaj’s unique soil.
Various post-volcanic activities also left their marks on Tokaj wine region’s geology. Hot water springs deposited significant volumes of alkalis (potassium and sodium) and a series of trace elements on the surface, enriching pulverized volcanic rock. Several eruption sites are located in the region, including Tokaj Hill in the Town of Tokaj, and Sátor Hill and Szava Hill in Sátoraljaújhely.
Tokaj’s current soil layers were formed the Quaternary period, with large amounts of airborne loess deposited in a wide swath on the southern edge of local hills. Steep slopes here have a thin soil cover, frequently mixed with fragmented andesite, resulting in a difficult combination to cultivate. In flat valleys, loamy scree, loam, and loess loam were deposited. The detritus from easily disintegrating rock glass mixed with this soil, enriching it with trace elements.
The current soil layers were formed the Quaternary period. Steep slopes have a thin soil cover that is often mixed with fragmented andesite and difficult to cultivate. In flat valleys, loamy scree, loam and loess loam were deposited. The detritus from easily disintegrating rock glass continues to mix with soil enriching it with trace elements.
The most common Tokaj soil type is clay mixed with broken-down rock (locally known as “nyirok”) made up detrital andesite and rhyolite tuff. Deemed to be the highest quality local soil, nyirok is slow to absorb water and is ideal for nurturing rich, and truly complex wines – in other words, a perfect natural fit for Furmint grapes. This typical Tokaj soil type has a reddish tint from iron hydroxide which grows darker in color with increased organic humus content.
Tokaj’s so-called “yellow earth”, a soil type formed from loess, is slightly less valuable than nyirok. Variations include slope loess, and loess loam mixed with scree, detrital rock, and fossil soil. Sandy loess is found only on Tokaj Hill and the hills north of the village of Olaszliszka. Yellow earth absorbs water easily, drains well, and has low lime content. Pure loess is largely absent from the region with the exception of Tokaj Hill where it stretches up as high as 1300 feet on the south-eastern flanks.
Tokaj is also home to “rock flour”, a thin soil formed from heavily silicified rocks and pumice through mechanical decay. Rock flour os composed of fine-grained white rhyolite detritus, pumice and perlite. It’s rather soft, lacks ductility, and does not hold water well. “Rock flour” has poor thermal capacities; therefore, vines grown in such soil are often exposed to potential damage from dry weather and frost.
Each type of Tokaj soil imparts a particular minerality to Furmint varietals; however, the extent and character of this mineral terroir varies greatly from wine to wine.