The solution for leaching is LYE, which is an alkaline substance composed of sodium hydroxide or potassium hydroxide. It is commonly used in a variety of industrial processes, such as soap making, paper production, and metal cleaning. In the context of leaching, it is used to extract minerals from ore, as well as to remove impurities from water. LYE is also used in food preparation, such as in the making of pretzels and bagels.