You must complete the Bolivia level before you can get the gold artifact. Otherwise, the rest of the manor will be closed off. Once you enter the manor, get the grapple located in the computer room in a safe behind Zip. To unlock the safe, use a laptop on the floor. After obtaining the grapple, get the pistols in Lara's bedroom. To get the pistols, there are two knives that both need to be pulled. Then, head to the library. To your right is a wall that can be broken by shooting it. Shoot it, then move the bookcase in the wall to one of the pressure switches on either side of Allister's desk and use the grapple to get down the other bookcase, which is above the pressure switch on the right. Put that bookcase on the other switch and a wall will open up. Grab the PLS on Allister's desk. Pull the switch in the dark hallway to make a large stone tablet with a clue come out of the wall. The clue reads "Above the Waters, Twin Sisters turn their backs one upon the other to leave the Ambages unguarded". Go to the end of the hallway and pull the second switch. Another wall will open up and lead you back into the bedroom. With the first clue in hand, go to the pool. On the right side of the pool there are two fish statues that can be pulled out. Pull them, then jump onto the shortest one. Jump on to the pole, swing to the ledge, jump to the other statue, onto the second pole, then onto the balcony. Rotate the two Greek statues so they face away from each other. Once they are in position, another clue will appear: "Within the Hall of Knowledge, Tomes of Cerulean, Topaz, Viridian and Crimson in turn reveal their Arcanum". Go back to the library. Push in the blue book to the right of the door. Then, go to the small room upstairs. Push in the yellow book, then the green book outside the room. Go back downstairs and push in the red book. After you do this, a wall will open that reveals the third clue: "Above the Hearth, revealed visage and countenance touched in haste raise up the Steward". Go back to the front lobby. To the right of the door leading to the library is a switch that just came out of the wall. Before you use it, use the grapple to pull out the poles leading to the other switch. After that, push the switch, swing to the other side, and use the other. The fourth and final clue then comes out of the wall: "The risen Athena turns to face the Sun, whose burden then reveals the Golden Laurel". A statue has arisen in the middle of the front lobby downstairs. Turn it to make it face the window above the stairs then stand on the pressure switch. The statue then goes back into the ground and a stone pillar with the Golden Artifact appears from the ground in its place.