Hahasako is eager to instruct you on procuring the corrupted crystals that you require.
Requirements
This quest is available if you have completed the quest Sealed with Science.
Starting the Quest
Talk to Hahasako on the wooden stairs on the east side of Highbridge in Eastern Thanalan to begin the quest.
Use the Maul to Fracture the Corrupted Cluster
Go east from Highbridge to the waterfall, and go into the tunnel to the left of it. Go through the tunnel, and when you go outside, go southeast until you can't go farther southeast. From there, go southwest until you can go southeast again, but when the path on the map splits three ways, make sure to go southeast. Then make your way down the spiral until you are at the level with water flowing past. Cross the blue crystal bridge to the northwest and you will find the sparkling Corrupted Cluster. Dismount and target it, then you can either examine it or target it and use the Quarrying Maul on it from the Key Items section of your inventory, or you can target it and use the icon to the right of the quest name in your list of active quests.
Use the Warded Pot
Target the Corrupted Crystal, then you can either examine it or target it and use the Warded Pot on it from the Key Items section of your inventory, or you can target it and use the icon to the right of the quest name in your list of active quests.
Present the Corrupted Crystal to Hahasako
Go southeast across the blue crystal bridge, then turn left and go up the spiraling slope, and make your way northwest until you can't go farther northwest. From there, go northeast until you can't go farther northeast, and finally, go northwest and go through the tunnel. Go west from there to return to Hahasako. Talk to him and hand over the heavy warded pot.
Present the Corrupted Crystal to Lamberteint
Go west to Camp Drybone and go down to the lower level, and go through the westernmost door. Turn left and talk to Lamberteint to hand over the heavy warded pot.
Next Main Scenario Quest
After you complete the quest, talk to Lamberteint to accept the next quest: A Promising Prospect.