Silver jewelry can oxidize and darken over time. However, you can use several different methods to fix this situation and polish silver jewelry. Here are some methods to polish silver jewelry:

1. Aluminum Foil and Salt Method:
   • Put hot water in a bowl.
   • Add a few spoons of salt into the bowl.
   • Place the piece of aluminum foil in the container.
   • Dip the silver jewelry into this mixture and leave it for a few minutes.
   • Gently clean the jewelry with a soft brush or cloth.
     
     
2. Lemon Vinegar Water Method:
   • Put hot water in a bowl.
   • Squeeze the juice of one lemon and add it to the water.
   • Add one tablespoon of vinegar to the water.
   • Dip the silver jewelry into this mixture and leave it for a while.
   • Clean the jewelry with a soft brush or cloth.
     
     
3. Silver Cleaning Solutions:
   • You can use silver cleaning solutions specially formulated for silver jewelry. Follow instructions carefully when using these solutions.
     
     
4. Toothpaste Method:
   • You can rub silver jewelry using toothpaste. Clean the jewelry using a soft toothbrush or cloth. Then rinse with water.
     
     
5. Silver Cleaning Cloths:
   • Silver cleaning cloths are special cloths designed to polish silver jewelry. Using these cloths, you can gently rub and polish the jewelry.
     
     Note: Before applying any cleaning methods, check the sensitivity of the gemstones on the jewelry to these methods. Also, if the jewelry has major damage or requires professional cleaning, consider contacting a specialist silver cleaning service.