Nearly forgot to post these! I've shown these carnelian earrings before when they were 'shiny silver'. At the time I felt like they might benefit from oxidising - so I took the plunge and ordered myself some Liver of Sulphur (how bad does that stuff smell?!), cleared a space in the shed and went for it!
Lots of polishing and a turn in the tumbler later - and I'm really pleased with the result! Still prefer shiny, but these have definitely benefited from the antique effect - I will be doing this again from time to time!