My gold band was showing lots of nicks and scratches, so I replaced it with a polished tungsten carbide band. The new ring cost about $20 and is as hard as sapphire - a couple of years later and it doesn't have a scratch.
Jewelry bought at retail depreciates substantially. If you really want to go grassroots, vintage/used jewelry may offer substantially more value. My wife and I have made friends with a couple of local jewelers who collect and sell vintage pieces, and my wife is a member in an active online community of jewelry fanatics who are always trading pieces.

