Amulet of Detect Poison and Disease

This clear quartz amulet hangs from a silver chain. The crystal turns green in the presence of poison and purple in the presence of disease, for example, if held over a plate of poisoned or spoiled food. The item will activate if within 30 feet of the affected item. The intensity of the color increases with the proximity to the affected item. The amulet has 2 charges, which reset daily at dawn. The wearer can use one of its charges to cast Purify Food and Drink.