Silver is especially susceptible to tarnishing via airborne, microscopic particles containing sulfur. Like fine silverware, it is more or less inevitable that it will tarnish in open air sooner or later depending primarily on its proximity to sulfur which is a common air pollutant. To keep them shiny it’s recommended to store them in an airtight container, which I have included. However, should they turn dark a brief wash in jewelry cleaner fluid should restore the shine. Weight of the 10mm cubes are 10.5±0.02g
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