calcium carbonate

(Newser) - Envelopes with white powder were found yesterday in eight federal buildings in seven different cities across Washington, Idaho and Utah, prompting the evacuation of an IRS building and a US attorney's office. The FBI is investigating whether the incidents were linked. "It is obviously disruptive and taken seriously,"...

(Newser) - Bacteria that secrete minerals are a well-known tool for "healing" cracked limestone statues, and the process got a Dutch scientist thinking. He theorized that concrete seeded with bacteria and a substance they transform into calcium carbonate would create a material that's able to seal cracks as they form. It...