The 'Diamonds' becomes dirty and cloudy looking due to grime and oil residues originating from fingers or skin contact. As the muck builds up on the surface, it can severely hamper the 'Diamonds' ability to transmit light properly.
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Even a thin film of oil on a 'Diamonds' facet can completely change the angles in which light refracts and reflects; resulting in lower brilliance and sparkle. This is why keeping a diamond clean is so important!
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Try soaking your ring in a solution of warm water and dish washing liquid for about 20 mins.
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Remove the ring solution and start cleaning it with a soft bristle brush. Clean all sides of the 'Diamonds' by brushing gently with the bristle brush. Since dirt normally builds up at the edges and the back of the ring in normal usage, you might want to give these areas an extra scrub.
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After brushing, place the ring back into the solution of water and detergent. Brush the ring. within the solution to wash off the loosened dirt.
Use a soft cloth to gently dry your ring.
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