Drying gold leaf in the drying oven

Noris Blattgold, a family-owned company in the fifth generation, and Memmert, now in the third generation, are two traditional Schwabach-based companies that have a lot in common. Both come together for the production of gold leaf.

There is a good reason why the city of Schwabach refers to itself as the goldbeater town. In the high middle ages, the nearby free imperial city of Nuremberg was a famous centre of metal processing. From the workshops of weaponsmiths, armorers, goldsmiths, watchmakers, wire drawers and precision mechanics, artistic craftsmanship found its way to all parts of Europe via the major trading routes. There are different legends as to why gold leaf-beaters settled down in Schwabach in the end so that, in the 19th century, 70 % of the population worked in gold-beating workshops. One legend states the dry climate which is needed for making gold leaf as a reason for why goldbeaters settled there, another tells that the strict requirements of the Nuremberg crafts ordinance had them leave Nuremberg for Fürth and Schwabach. Probably, there is a little bit of truth in both stories. Today, what is most remarkable is that the last five remaining gold leaf factories of Germany are all located in Schwabach. With more than one hundred employees, Noris Blattgold is the largest of them. 

An oasis of gold leaf beating

High-purity gold and secret ingredients are melted into different alloys at above 1200 °C and then, bars 4 cm in width are cast.

High-purity gold and secret ingredients are melted into different alloys at above 1200 °C and then, bars 4 cm in width are cast. 

 

Pomp and pageantry of historic churches, castles and paintings would not be possible without gold leaf and even for modern architecture, landscape gardening or art, the timeless precious metal is indispensable, since nothing can replace it. For this reason, especially conservators, frame manufacturers, church painters, artists and architects are customers of Noris Blattgold with their worldwide unique wide range of products: Gold leaf in 32 different colours, roll gold, powder gold, shell gold (and all that also in silver), tools, lacquers and even edible gold and silver. Armin Haferung, responsible for managing the company founded in 1876 in the fifth generation, is the last master goldbeater of Germany. In the future, Noris Blattgold will therefore be some kind of oasis in which the gold leaf beating tradition lives on, is passed on and, of course, further developed in terms of modern manufacturing. 

Gold leaf today: centuries-old tradition and modern technology

Memmert drying ovens for drying and temporary storage at Noris Blattgold

Memmert drying ovens for drying and temporary storage at Noris Blattgold 

 

The process of gold leaf manufacturing has hardly changed since the middle ages. After alloying the high-purity gold with secret and exactly measured ingredients at above 1200 °C, bars 4 cm in width are cast. This way, poetic colours such as Versailles Gold, Green Gold dark and Moon Gold or pure 24 carat gold are created, depending on the recipe and striking tool used. On a guided tour with Armin Haferung through the production at Noris Blattgold, modern technology can be seen and heard especially with the rolling mills, which press the gold bars into 0.007 mm thin foil strips and with the automatic beating machine, in which the actual beating is done fully automatic in contrast to the manual work in the middle ages. The gold foil strips are cut into gold foil squares of 16 square centimetres, placed between plastic sheets and then beaten in layers of 2,000 sheets to a surface of 196 square centimetres. In the end, the extremely thin gold leaf is only 0.007 millimetres thick. In contrast, a human hair with a thickness of between 0.004 and 0.1 millimetres seems like a rough hemp rope. 

During a tour of the production area at Noris Blattgold, Memmert is yet another traditional Schwabach-based company one encounters. Rolling and beating of the gold foil is done in several passes. Therefore, the beaten material has to be dried and temporarily stored for several days in a drying oven at temperatures between 52 °C and 85 °C. Even the chalk powder used on the divider sheets to ensure that the gold leaves can be easily removed from the surface is stored in Memmert drying ovens. Despite the powerful machines, gold leaf beating is still mostly done by hand. No machine would have the necessary sensitivity to place the gold leaves in little square books with 25 sheets of tissue paper each before the journey of the gold continues.

AtmoSAFE wants to thank Armin Haferung, manager of Noris Blattgold as well as photographer Salvatore Giurdanella for their kind assistance in writing this article. The picture of the “Gold Roof” on the Schwabach city hall was photographed by Irene Ramspeck.

The gold leaf which is beaten extremely thin is placed on tissue paper by hand

The gold leaf which is beaten extremely thin is placed on tissue paper by hand

Ageing in the heating oven

At Leoni AG, wires and cables undergo tough tests in the heating oven during the simulation of ageing.

more information

 
An overview of the main topics
  • Drying oven
  • Universal oven
  • Gold leaf 
  • Noris Blattgold 
  • Schwabach
  • Goldbeater 
Laboratory appliances for drying

Heating oven (drying oven) U
Vacuum drying oven VO