Morning RDV,
Last night the images did not show up and we were looking at blanks. Hence my wake up call and the result of some perfect images.
The marks;
The hatchet:
not a standard mark for fineness. The books show two forms: 1)1798 the poincon de vieux, poincon de hazard or second hand mark duty mark. When an object was returned to the trade, in accordance with the rules it had to be re-submitted to the assay office for verification of the marks. When it proved that the marks on the object were still valid, the hatchet was struck as a formality free of all charges. The archives have proved that the rather murky legal provisions on this mark were often misunderstood by the officials. By 1812 the requirements for this certificate had become a dead letter and this mark was rarely used any more. The purpose of this mark is thus different from that of the later hatchet mark used 1853-1927 duty mark for old gold and silver objects of national origin returned to the trade. This hatchet was intended for objects with the hallmarks of the ancient Netherlands goldsmiths companies, of Louis Napoleon’s kingdom of Holland, of the French Republic, of the French Empire until the end of 1813, of Maastricht and Liege 1814-1815, and of the former Southern Netherlands considered national and thus exempt from import duty . The use of this mark was abolished in 1927 for two reasons: 1st. the lack of knowledge of the old marks had caused this mark to be sometimes struck on old foreign objects.2nd. This mark has often been counterfeited and used to give objects an antique aura. The difference with the older French hatchet mark: The French mark was struck tax free on objects with valid hallmarks. This Dutch hatchet was struck, also as an indication of marking duty payment on objects with hallmarks which were considered fiscally valid. Where are your valid hallmarks?
Your Crowned O misshaped most probably a fake duty mark.
Your date letter is a B and not the Dutch date letter R for 1826, please look at your own image of the R for 1826 and notice the differences.

Please look at the picture of the date letter B for Rotterdam and notice the differences with your letter B. Closely examine the city mark of Rotterdam and please draw your own conclusion.
Regards,
Oel