This is a nice Solid Sterling Silver Pendant or Key Fob in the shape of an Ingot.
It is hallmarked with the assay mark for London, Queen Elizabeth's Jubilee Head, the date letter C for 1977, and the maker's mark K over MJ.
Very good vintage condition, just light scratches and a small scrape along one edge which you can see half way down the left hand side in the last photograph. The hallmarks are clear.
The ingot is 3.6 cm x 1.9 cm, and it weighs 31.2 g gross.