You need to drop a piece of coral in Charl's shrine. Any piece of coral you have foundpreviously will work, otherwise you will have to kill creatures or whatever means you have to get gems. From Wehnimer's North Gate, go NW, NW, NW, go road, W, W, NW, W, W, W, NW, NW, W, W, SW, W, W, W, SW, W, go path, E, down, down, down, go boulder, swim opening. This puts you in Charl's shrine. There drop the coral and you will get your completion message. Return to the monk and he will instruct you in the Symbol of Throw.