To make diamonds shiny again, soak them in a glass of club soda overnight. In the morning, your jewelry will be sparkly again
Use a paste made of baking soda as mentioned above. Then, pour a bit of vinegar over the jewelry, rinse and pat dry.
Drop one tablet into a glass of water. Place your jewelry inside and let it sit for a few minutes. Remove it and rinse to see it shine again.
Squeeze a bit onto an old, soft toothbrush and scrub your diamond jewelry gently with it. It will sparkle, just like your teeth do after brushing.
Vodka will clean any type of jewelry. Dip your diamond jewelry into a shot of vodka for a few minutes and watch it sparkle again.