I have included a ruler and a normal tea sized spoon to help you guage size of this magnificent silver server.
The caption says :
The statue and plinth are atop the Imperial Prussian eagle and crown
There are two marks with a wiggly line between them.
A wiggly line often means that the silver was assayed at that point, but I suspect that this is a pseudo mark because of the location of the other marks
The marks trace this spoon to J.D. Schleissner and Sohne of Hanau, Germany ca. 1876 - 1900
This firm was known to use sterling silver, (but also used lesser grades of silver) and they also exhibited at the 1893 Chicago Worlds Fair and again at the 1904 St. Louis worlds fair.
The finial, stem and heart shaped bowl appear to be cast with hand touch up.
The finial shows an elaborately costumed Frederick with a triangular shaped hat and holding a riding crop in his right hand.
The left hand is in his pocket. The sword is surrounded by epaulets. The boots are a dress variety and do not have spurs.
The back of the finial is nicely finished and shows his long hair 'pony tail style'
This very large spoon pays tribute to a very important king.
This is a 1/3 Taler Prussian coin bowl from the era of Frederick the Great, struck at the mint in Breslau and is dated 1773.
Note: this is a .666 fine silver coin that has been gold washed.