Argentium silver.  Approx pendant size 55x25mm.
 
I have a Rowan tree growing outside my door (every house should have one as the Rowan is renown for protecting against witches!) and I was struck by the beauty of its leaves and recreated them on this amulet style pendant. 
 
Argentium silver is a relatively new silver alloy with germanium being added to the mix.  This makes for a whiter, brighter silver, with very strong tarnish resistant properties, it is also very ductile making it idea for chasing and repousse projects.  Although higher in silver content (935 parts per 1000 as opposed to 925 parts per 1000) than sterling silver, Argentium silver is currently hallmarked by the London assay office using the 925 sterling silver standard.