Horn coral fossil from the Mid-Ordovician period called Rugosa or Tetracoralla coral,,long ago extinct,,sized jumbo.This horn coral piece has classic shape and is agate hard so it takes a great polish.These coral most likely came from large colonies of coral that now can be found in fossil beds of the anti atlas mountains in northern Africa.The coral has long ago agatized or fossilized but still retains the coral pattern and horn head and that is what makes these pieces unique in the horn coral family.This material can be polished to a great shine and cut to see some coral pattern or just studied as it is.