text: The history of who first devised the process is unknown. What is known is that from 1870 onwards, a number of patents were filed for the process. Although all patents appear after 1870, it has been suggested that the process may have been discovered earlier, and the patents claimed a short time afterwards. The most well known patent holders are Frederick Shirley from the United States of America, whose patent dates to 1879, Erard and Round who were under the auspices of Stevens & Williams Ltd. whose patent is from 1889, John Sharling also of the USA, whose patent is from 1893 and Friedrich Deusch, the German inventor whose name is most associated with silver overlay today,  whose patented the process in 1895 and displayed his work in 1907 at an exhibition in Bordeaux.
  Deusch returned to Schwäbisch Gmünd in southern Germany where, in 1912, he founded his firm Deusch & Co. Deusch continued exhibiting his wares and gained the Gold Medal at the 1913 World Exposition in Ghent, Belgium.
  With his presence, Schwäbisch Gmünd became the center of German silver overlay production. Schwäbisch Gmünd (about 20,000 inhabitants in that time) had a long tradition since the 16th century in the art of artists working with gold and silver. A school for applied arts existed there from an early date, which became a school for the precious metal industry in 1907. 
  In the 1920s almost 190 firms were involved in the precious metals industry. The presence of materials, artisans, and component suppliers in on place created an ideal environment for the industry to thrive.
  After Deusch and Company, other firms specializing in silver overlay were founded. In particular, the firms of Friedrich Wilhelm Spahr and Alfred and Manfred Veyhl were established.
  Parallel to the development of German silver overlay, silver overlay production was also initiated in the United States.