It is in one of the chimneys on top of Thomas Edison's house (9 o'clock, 1877 AD). To reach it, start the "horseless carriage" at far left and ride it across to the tree.
The Aztec Empire is where you get the sun stone piece on Time Tangled Island. It is 1519 AD the picture is a man with headdress.
The sun stone in Time Tangled Island is located in the ancient city of Tenochtitlan, which corresponds to the Aztec civilization in Mesoamerica.
The piece of the Sun Stone is from the Aztec kingdom at 1519 AD (5 o'clock on the time device).
It's on top of the house of the guy who makes the telegram, sticking out of the chimney.
The colorful piece of stone (part of the Aztec Sun Stone) is on top of Edison's house (1877 AD). Return it to 1519 AD.
In the Aztec period, you get them from the warrior.
It is on Time Tangled Island. You will get to it when you retrieve the golden stopwatch to travel in time.
To find Edmond's goggles (in the Aztec time).
It's on top of Edison's roof in 1882 AD, where you return the phonograph. Bring it to the king at the Aztec time, 1519 AD.
It is part of the Aztec Sun Stone (1519 AD). Take it there and return it. If you get the warrior mask from the far right, the guard will give you the Climbing Goggles for 1953 AD.
on the top of the tower thing.
It isn't necessarily gold, just a brightly colored piece of the Aztec Sun Stone. At 1877 AD, click to start the engine of the early motorcar, and it will drive to the right, under the tree. Climb the tree and onto the roof of Edison's house to find the sun stone piece in a chimney (one of two). Return it to 1519 AD.