Ok this is just a theory, but the French minted a new silver coin in 1849, and I believe the marks on this fork are to signify the fact that it was made from French silver coins, which bear a very similar "6-Pointed-Star" and also the laurel wreath looks like the "fern" symbols on my fork:

Some researchers have theorized that these "flourish marks" or "countermarks" or "counterstamps" or whatever you want to call them, had something to do with the types of coins which were being melted down in the manufacturing of the flatware, so perhaps the symbols are somehow related to the French Silver Coins which were first minted in 1849. 1849 is a good starting date for this fork, I would date it 1850-1860, right before the "Sterling Standard" became common in America and Coin Silver began to fade from the population of silver objects....