Thomas Law registered a mark on September 11^th 1773, the day the first marks were registered at Sheffield.

His mark is very distinguishable as he chose to use his full name as his mark. He marks his name on one arm and an abbreviated “TL” mark on the other. This “TL” mark is often in an unusual serrated edged punch.

Thomas Law was also a maker of Sheffield plate and the marks he used on plate were either:

"TL" along with THo "LAW". or
"TL" along with "LAW".

In examining the various publications regarding the Thomas Law maker's mark, in particular the Sheffield Assay Office register, we see that his mark for silver was "TL" with "T.LAW". It is noticeable that the punch depicted does NOT have serrated edges. From the pairs of tongs below, we can clearly see that he used both the serrated edge "TL" punch and the "TL" punch without a serrated edge.

We do know that there were a number of Sheffield makers that made both solid silver and silver plate. It seems that the Assay Office was not always too concerned which of the maker's marks were punched, (Deakin Smith & Co. are another case in point as their maker's mark on the solid silver tongs shown is also not the mark registered in the Assay Office Register).

Clearly it is much more important to see the Assay Office Lion Passant to determine whether an item is solid silver. This is the true determination - not the maker' mark.
Thomas Law sugar tongs are quite rare.