This is very nice fossilized Coral specimen from Iowa.  The all natural surface has many genetically identical agatized coral polyps.   This very interesting fossil shows great character as shown in pictures linked below.  This unique specimen measures nearly 6″ x over 5 1/4″ tall x almost 2 7/8″ and weighs almost 3 1/2 lbs.  A must have for the fossil collector or an excellent gift for someone!