To clean diamonds, soak them in warm water with a few drops of dishwashing liquid before gently brushing them with a soft-bristled toothbrush. This toothbrush should be used only for cleaning your diamond jewelry, and for no other purpose. Rinse them in clean water before wrapping in paper towels to dry.
https://www.biltmoreloanandjewelry.com/blog/how-to-care-for-different-types-of-collectibles/
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