Inconsistencies  
There are two inconsistencies. At one paragraph the article claim the fulgurites can reach a length of 15 meters, implying there have been one found with that length. Further down the article I read the longest one found is around 5 meters. Which one should it be?

"Fulgurites have often deep penetrations, sometimes appearing up to 15 meters (50 feet) below the lightning-struck surface."

"The longest fulgurite found is approximately 4.9 to 5 meters (17 feet) in length, and was found in northern Florida, USA."