As you can see, it is a feather edge teaspoon with bright cut decoration and has the Dublin Harp and Britannia hallmarks dating it to 1793 - 1796 far as I can tell from Jackson's Hallmarks. You will note however the lack of date and maker's marks and I wonder why the Dublin Assay Officials punched the harp and Britannia but omitted to punch the date mark while the goldsmith also did not punch his mark, usually done before sending the silver piece to the Assay Office.
In this respect, I am reminded of John Luddington's remarks in his excellent book Starting to Collect Silver "Up to the third quarter of the eighteenth century, the assay officials and goldsmiths of Dublin seemed consistently unpredictable in their use of marks. Thus, the beginner who is still unable to determine date by style is liable to become confused". Consistently unpredictable is a wonderful turn of phrase by Luddington! Seems though the unpredictability of the Dublin Assay Office and goldsmiths extended to the last quarter of the eighteenth century as well!
Before checking the marks in Jackson's, I had thought c. 1780 for the spoon so I wasn't too far out. Note that on this spoon the harp and crown are completely separated while in Jackson's there is a sliver on the right side connecting the two. Bennet also seems to show the harp and crown touching at this point.

