Start:Talk to the Observatory Professor in the Observatory Reception Room west of Tree Gnome Village.
Requirements: Level 10 Crafting, ability to defend against level-48 Goblin guard.
Items needed: Bronze bar, molten glass, 3 planks. A Cure poison Potion is also recommended.
Talk to the Observatory Professor and ask to look through his telescope. He tells you that the Goblin residents have been causing trouble and tampered with it. He asks you to collect 3 different items. Hand in all 3 items, and he will return the molten glass while asking you to find the lens mould.
Go down the ladder in the Observatory post, into dungeon. Go through the maze to the far south west corner and you find a chest containing a keep key. Go to the room where a level-48 Goblin guard is, the room is located east from the entrance to the dungeon, kill him and use key on the gate. Search the sacks to find lens mould.
Go back to the Observatory post and give the lens mould to the Professor. Agree to help him make the lens. Use molten glass on the lens mould and then talk to the Professor and he will tell you to meet him in the Observatory.
Go back down to the dungeon, and through the maze, and find another ladder north of the chest containing the key to the gate. It leads to the Observatory. Talk to Professor and look through the telescope to complete the quest.
Optional: Unholy symbol mould
Look into the telescope again and you will see a strange symbol. Speak to the Spirit of Scorpius, at the graveyard to the north. He will give you an Unholy Symbol mould, which you can use to make Unholy Symbols of Zamorak. If asked, he will also bless these symbols.
2 Quest Points
Crafting experience = (Level x 100 + 250) x custom rate