It’s an old folk song, old enough in America to perhaps have come from Britain; there are variants aplenty. But for most people today, including me, Silver Dagger is that Joan Baez song. Ms Baez has a beautiful voice, great skill in using it, and (maybe most important) fabulously good taste in picking what to sing.
Here’s the cover of her debut album from 1960. It’s my own photo of my own copy. A little sticker in the corner reveals that at some point I paid six dollars for it.
I don’t know if this is my fave by Ms Baez; you have to think of El Preso Numero Nueve and Diamonds and Rust (which by the way she wrote). But it’s a classic, and works so well in that just-a-singer-and-a-guitar mode.