Thank you, Trev, for posting a much clearer image of the marks.
I believe the second mark to be the lion found on the Sinhala or lion flag of Sri Lanka. Another version of this mark appears on a tray that is definitely from Sri Lanka, insofar as the tray itself is in the shape of the island of Sri Lanka, and it has a personal inscription from the early 1950s tying it to Sri Lanka.
There seem to be a few versions of this Sri Lankan lion mark, so I would suppose it is a geographical or national mark applied by the manufacturer and not a purity mark per se. I would guess it came into use around the mid-twentieth century, after the end of the Raj. Ceylonese silver produced in the colonial period seems to have been mostly unmarked and much more finely finished.
Furthermore, the same mark, KAA, appears on another dish with the same circle of animal motifs that is claimed to be from Sri Lanka.This design of various animals in concentric circles, much abbreviated on this box, apparently refers to a large carved moonstone at the Anuradhapura palace.
As for the question of purity, it always seems pointless to discuss where Asian silver is concerned. If purity really matters to the OP, then s/he can have the item in question tested by any number of methods, none yielding such absolutely definitive results as the melting pot. If the OP does test the piece, hopefully s/he will share such results with the Forum.