see the Online Encyclopedia of Silver Marks, Hallmarks & Maker's Marks  or  900-1000.com

As I see so many mistakes in listings by purpose or not of Dutch Silver I shortly explain Dutch Silvermarks

90 is often called a Hallmark or Sterling Silver but it stands for silverplated, as well as 100 stands for silverplate

the logo DE or DE are the initials of the tea and coffee factory Douwe Egberts in Joure (Fr) Holland and the articles with this are often marked HH 90 which stands for Hooikaas, Schoonhoven and silverplated

most  Dutch silver articles  have a hallmark and a makersmark a yearletter and an assay office mark

I've seen listings with 15th, 16th or 17th Century silver, while the Hallmarks clearly indicate it is made after 1800

especially dutch silver articles made in the late 1800 have false or pseudo marks, although it is silver and marked so

the so called Hanau marks that look like old Dutch hallmarks are explained elsewhere as well

an example is a Sterling Silver Server Spoon Open work  Amsterdam ca.1846  that sold February 25 2009

I sent the seller 2 days before auction ended information about the yearletter: M stands for 1948, the makers mark Z achs Z (Zaanlandian Silversmith:Zaanlandse Zilversmeden) was not used before 1920, She said appreciate your remarks, but did not change the description or title

you can find Hallmarks and Silvermarks on the above mentioned Encyclopedia

selling silverplate for (sterling) silver is of course all over the world against the law with severe penalties, eBay doesn't care although they say they want to create a safe enviroment for selling and buying