How to stamp a hallmark

 Ruth, I don't know if this is practical for you, as I haven't a
clue what type of work you are doing, but I have a clever friend
who hallmarks a separate sheet of metal, then cuts out a little
piece with the hallmark on it from this sheet, and solders it to
her piece near the end of construction.  Solves the dent problem,
and it looks really sharp. Danny 

This is a slightly dubious technique and wouldn’t be accepted as a
true mark of purity in the UK. Here, the only part which would be
accepted as of the purity marked would be the tag itself. Under the
British system each part of the construction would have to be tested
(assayed) and all the major pieces would have a separate mark. At one
time - maybe still even today - it was the practice amongst the
‘underworld’ part of the antiques trade to cut the hallmark from a
small genuine article and solder it into a recess on a ‘fake’
antique, either to give it ‘age’ or to make the metal seem like
better quality than it was. As a result, one of the first things you
do when looking at a piece of, say, silver plate to buy, is to
breathe on the hallmarked area to see if a solder line shows up!

Best wishes,
Ian W. Wright
Sheffield, UK