The pendant is not stamped nor signed but has been tested to confirm it is sterling silver has a blue gem which I don’t know if it is glass or gemstone then there are little stones I don’t know what color if they are supposed to be dark color or they are just darkened due to age either way this is a gorgeous piece I wore it for long time I never took it off. The chain is not stamped but clasp is replaced looks to be if I’m not mistaken I believe it is sterling but I could be wrong as the chain is untested but you could always change the chain it’s on. Measurements are shown in above photo for chain and pendant 1900’s Antique Diamond like shape Has wear and patina Display Box Not Included