The Kansas City Star
Photos of a mysterious “bright blue mineral” discovered in a historic Michigan copper mine have piqued the attention of many as what it is remains unidentified. The mystery substance was captured on rock walls of Adventure Mine’s third level near Greenland, Michigan, photos posted on Facebook show. “This bright blue mineral has not been positively identified as of this post but it is a secondary mineral that is caused by a reaction with air and water,” mine officials said on Sunday, Dec. 26.