Sterling Koch & Bergfeld solitaire flatware set

The set comprises four pieces
-Dessert spoon
-Knife
- Fork
- Spoon
All are marked with the German hallmarking system unified in 1888 (see Decree January 7, 1886) adopting the national mark "crescent and crown" indicating in thousandths the fineness of silver. This system is still in use in present days. http://www.silvercollection.it/germansilverhallmark2.html and the makers mark of Koch & Bergfeld used since 1884 to 1980 http://www.koch-bergfeld.com/besteck/hallmarks.php. In this same web page there is a lot of information about the company “Koch & Bergfeld is one of the world's oldest producers of silverware still in operation: since 1829 silversmiths from Bremen have unflaggingly manufactured cutlery, silverware, championship cups and plaques for lovers of silver on five continents. They include the world's first royal houses, well-known merchants, large companies, governments – not to mention collectors and many people who just like dining off silver...Over 300,000 different designs – including more than 15,000 different pieces of cutlery from a good 350 models in total – produced by the firm's so-called "Design Office" are all recorded in books, filed as drawings or even kept in safe storage as prototypes.” Really impressive. The knife is marked with the Solingen mark of ZWILLING J.A. HENCKELS and the twins. Wikipedia says On 13 June 1731 Peter Henckels registered the "Zwilling" (German for "Twin") logo with the Cutlers’ Guild of Solingen. This makes Zwilling one of the oldest trademarks in the world. 40 years later, Peter's son Johann Abraham Henckels (1771-1850) was born, who would later re-name the company after himself. The Henckels logo has been in the current shape with a red background since 1969. Thus the set is between 1900 and 1969 by the marks, http://www.j-a-henckels.com/en-WW/Company-profile--company_profile/Chapter--kapitel/The-history-of-the-ZWILLING-J.A.-HENCKELS-brand--401.html.
Because of the velvet, the steal of the knife blade and the shape I would say it was done about 1930 about the great crisis. Sure it was a present for a graduating student or something like that, I have a similar set that was given for my 6 birthday as a present by the sister of my grandmother (she was born in Poland).