The tongs are certainly in the right forum, but whether Chinese or Japanese may require further research. The tongs surely date from about 1895-1915, a time of intense borrowing (or perhaps copying) back and forth between Chinese and Japanese export silver makers vying for international trade. The iris design was particularly popular and makers in both countries produced it.
There is a Chinese maker, YK, as far as I know unidentified, but the marks I've seen are either YK in capital letters with serifs or YK in caps without serifs and also without the dot as seen on the tongs.
There is also the possibility that YK is a Japanese maker, as so many Japanese names begin with Y and K. For instance, Y. Konoike is a well known maker of this iris design of tea service, but I have never seen his mark in roman letters, always in Chinese characters (for a example of his mark, see page 3 the Chinese and Far East Trade section of the Contributors' Notes.) Furthermore, Japanese tend to insist on their names being romanized in the same order as Japanese, i.e., family name followed by given name, which would then become KONOIKE Y or KY.
The 950 fineness suggests Japanese silver, which usually was of very high fineness, and the overall design gives me the impression of Japanese silver. Even so, as this type of roman-letter maker's mark points toward Chinese silver, my personal opinion at the time of this writing is that the tongs can be attributed to the as yet unidentified CES maker YK, perhaps borrowing from a Japanese design.
Please bear in mind that this is only one opinion, and a tentative one at that. Someone else may provide a more definitive answer.