Whats better than a signet? a signet with a slug on it, thats what.
Signet cast in solid sterling silver, with a Bronze Slug on top.
After a while silver can tarnish and go dull, a quick buff with a polishing cloth can bring the piece back to a shine.
If your jewellery needs cleaning further, silver cleaning is pretty simple: warm water and washing up liquid and a quick scub with a soft toothbrush will get rid of most common dirt and grime.
Bronze wont stay shiny forever, it will tarnish and age. but this can be repolished with a polishing clothe. or just by wearing it everyday.