Related Clues:

• Slow flow
• Tree whose winged seeds look like tiny canoe paddles
• Igneous rock source
• Gray tone
• Can opener?
• Pompeii was covered in it
• Volcanic effluent
• Result of burnout?
• Gas-grill rock
• Hot flower
• Havana residue
• Fire sign?
• Sweep's take?
• Wood used for baseball bats
• Rock that rolls?