The ingredients of this recipe are simple, clearly identifiable, and readily obtainable, so we can replicate the process today. After the ingredients are mixed (I found that urine works better than vinegar, by the way) and boiled gently for about an hour, an orange-red and unpleasantly scented liquid results. Although the Leiden Papyrus does not say how to use the liquid, we can guess. When a polished piece of silver is dipped into it, the metal quickly becomes tawny, then golden, then coppery, then bronzy, purple, and finally brown. Impressively, the shiny brilliance of the metal remains
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