Many unknown treasures and concretion-encased surprises await researchers on the wreck of Blackbeard’s flagship, Queen Anne’s Revenge (QAR), near Beaufort. Part two of this year’s dive season resumed this week, and the plan is to recover artifacts from 60 five-foot by five-foot units by October 31. After nearly 300 years on the sea floor, the artifacts often are locked in a concrete-like crust of sand, shells and marine life that is removed during the conservation process. This summer’s earlier dive ended in mid-June with the recovery of two eight-foot cannons.