Where should I sell my old ring and tires?

I have a white gold (or platinum) ring with diamonds that I want to sell. I bought it 20 years ago, and some of the tiny diamonds are gone. Is the place like "cash for gold" best place to sell it? Pawn shop?

I also want to sell 8 snow tires off 2005 Ford explorer that I bought 4 years ago and are in very good condition. It's harder than I thought to find a place to buy used tires. Any recommendation? Craigslist?

The ring try a pawn shop
the tires yah craigslist or a note at your local grocery store bill board