Related Clues:

• Volcanic outflows
• Molten flows
• Dangerous streamers
• Aa and pahoehoe
• Volcano emissions
• Liquefied rocks
• Volcanology specimens
• Volcanic flows
• Volcano's flows
• *Aa and pahoehoe, for two (or the other way, like military fleets)
• Stones that make up Northern Ireland's Giant's Causeway, e.g