Do you need a buffer to get a shiny finish on jewelery?
No, you definitely don't need a buffer


Image from Wikimedia Commons

This gold belt buckle dates from the 6th century - long before buffing machines were invented. Finishing jewellery by hand is the traditional way to do it, and as you can see the results can be excellent.

However, you can't get this kind of finish just with sandpaper

Going up through the grades of sandpaper is a good way to start, but to achieve a truly smooth finish you need something finer. There are a few different things that are available now for final polishing, but the traditional one is ferric oxide, also known as jeweller's rouge.

You can use this by applying a little to a polishing cloth, and polishing the piece until it's done (you'll need to wipe the rouge off afterwards)