When sulfuric acid was dripped onto the crystals they fizzed and released what is likely carbon dioxide gas. This indicates that the crystals contain calcium carbonate.

When sulfuric acid was dripped onto the crystals they fizzed and released what is likely carbon dioxide gas. This indicates that the crystals contain calcium carbonate. Image courtesy of Thunder Bay Sinkholes 2008.

 

Related Links

Thunder Bay Sinkholes 2008

Thunder Bay Sinkholes 2008: Sept 4 Log

NOAA Ocean Explorer Gallery