Bluish white, brittle heavy metal or element (Zn). The name is derived from zinc (tooth, jag), as zinc solidifies in a jagged shape. It occurs relatively frequently in the earth's crust, although not in pure form (solid), but only bound in ores. The most important ores for zinc extraction are zinc sulphide ores. Zinc is essential for all living organisms and is a component of important enzymes. It is very important for the healthy growth of the vine. Zinc deficiency occurs particularly in sandy soils. Soils with an extremely high phosphorus content are also at risk, as an increased phosphorus supply to the vine can hinder the absorption of zinc.
Lime-rich soils or high calcium content also tend to lead to zinc deficiency. This leads to disturbances in flowering and fruit set, poorly lignified stem structures and weakly developed shoots. The leaves have sharply serrated edges and open stem bays with elongated, narrow leaves. This is often accompanied by chlorosis. Treatment is carried out by spreading zinc paste on pruning wounds or by spraying the leaves. The use of galvanised wires and sticks in the vineyard can lead to a large surplus in the soil. Too high a content in the wine leads to cloudiness and a metallic-bitter taste. The perception threshold is 5 mg/l. See also with regard to other metals under Black Break.