Related Clues:

• Fire waste
• Eruption evidence
• Grate collection
• A smoker may flick it off
• Barbecue by-product
• Campout fallout
• Holy Wednesday forehead marker
• It buried Herculaneum
• Butt remains
• Briquette residue
• Old flames?
• Common tree
• Dusty remnant
• Incinerator product
• Eyjafjallajökull output