These are treasures I found on the Thames foreshore when I lived London. The tiny dark stones are garnets. The Thames seems to be full of those - perhaps a cargo load was lost at some point.
My favourite treasure is the little button on the same pottery piece as the garnets. Someone did once date it for me but I can't remember what they said now - maybe 1600s.
Blipping this because I'm at home this morning, rather than Mum's, and it feels really good to wake up here among all my own things.