Hi, theres a beautiful Eduard SS Star for sale right now on Collect Russia site. Lots og good pics of exatly what to look for in a 1900 1910 issue. Keibel issue pieces were mainly the same in dimensions. except thiese were a bit flatter in style the Eduard pieces were higher in the center. There were other makers outside of Russia some marked some not. Please post pictures of your piece someone may be able to help id maker I'm not a silver expert but I think russia hallmarked all there pieces. George