Related Clues:

• Smelter residue
• Surface residue
• Fruit of the oak
• Waste at a foundry
• Bathtub woe
• Lees
• Blast furnace byproduct
• Pond film
• Ugly film
• Bathtub dirt
• Smeltery by-product
• Icky residue
• Winery leftovers
• Settled matter
• Refined waste