Hi SilverK,

There seems to be a little confusion, for Rotterdam year 1805 the letter is
ij in English you call it Y.
The various different year letters used by the city guilds are not online (yet). Tardy does not provide the necessary in depht information needed.
What I thought to be the maker's mark is actually a French import and duty mark
& =ET = étranger= foreing.
From the hallmarks of the French Empire 1809-1819
This mark also used as tax free census mark, without guarantee on the standard of fineness. This mark also occurs rather frequently on objects bearing the older marks of Dutch guilds and the duty marks of the Kingdom of Holland, and the 1807-1812 Kingdom of Holland proper hallmarks.
Résumé; The belt hook is made in Rotterdam during the French occupation of the "Netherlands", assay year letter
ij for
1805 and in
1807 up
for sale, hence the
Crowned O.
In March 1807, by order of the King of Holland, a new hallmark law on the working, importing and sale of gold and silver objects, including the levy of duty on the same was implemented. Silver smiths, retailers and silver- shop holders could, for a few weeks, bring in their old hallmarked and previous made silver & gold objects and have those objects stamped with the crowned O, the capital letter O for the Dutch word 'Onbelast=dutyfree; free of charge and no tax Duty.
After this period, a tax duty had to be paid and the crowned B was applied, the capital letter B for the Dutch word 'Belasting'=Tax. After the 18th of April 1807, officially no work with old hallmarks was allowed to be sold without the crowned O, unless tax was paid and the object stamped with the crowned B. Somewhere between
1809-1813 when the "Netherlands" were part (province) of the French Empire the belt hook came up for sale, hence the
& = ET= foreign duty mark.
Again somewhere between
1814-1893 Kingdom of the Netherlands-present the belt hook came up for sale in a shop or during a public auction, hence the
Crowned V.Crowned V for large items; duty mark for foreign and other untaxed objects used 1814-1893. This duty mark does not give any guarantee of a precious metal standard of fineness. This mark has been used on metal with a 250 minimum silver content as a duty mark. This mark was destined for all imported, unmarked and invalid marked objects of foreign, national and unknown origin. Upon the invalidation of the hallmarks of Louis Napoleon's kingdom of Holland and those of the French Empire in 1816, this mark also has been used as a tax free census mark. This little belt hook tells us a great historical silver story!
The maker's mark, I am afraid is on the curve of the belt hook. We need an image. I will go for a stiff G&T.
Peter.