One method is to make a mixture of white vinegar, flour, and salt, then apply it to the jewellery and rub it lightly. Then rinse it with water and pat it dry with a soft cloth. Finally, apply a few drops of oil and vinegar to your jewellery gloss.
Before you begin, soak your jewellery in warm water with green soap to soften it.
Another method is to squeeze lemon into a bowl and add salt. Dip a cloth into the bowl and rub your jewellery.