Look above the golden mask to the left of the sarcophagus. It is a bit behind the mask, and the top edge of the cube is horizontal.
Level 10 hidden items
Hidden items can be found in the following locations.
On a shelf in the back left.
Below the stack of books at the left edge of the screen.
The golden toucan statue is sitting on one.
Behind the stem of the large goblet in the middle of the bottom edge of the screen.