The other day I bought this wheel second hand. The spokes obviously need cleaning.
I am not interested in super shiny spokes. As they original were, is good enough for me.
Above all I want to avoid options that although may first result in very shiny spokes, but thereafter will require frequent maintenance to avoid rusting.
I have been suggested a few options:
Clean them with tin foil and some water.
Clean them with tin foil and water with some salt added
Clean them with tin foil and water with some vinegar added
But maybe you have better suggestions