Of blue bloods and silver spoons

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Aristocrats were originally the only ones who could afford medicine, often in the form of colloidal silver (the liquid into which silver particles are suspended and was thought of as a cure-all for many different illnesses); could have a considerable number of silver coins and could have worn silver jewelry; and could have eaten off silver plates and used real silver cups and tableware which were later found to shed nano silver particles under a microscope. Hence, argyria was common only to those who were born with a silver spoon in their mouths.