Move up once and you will see a pot on the left side of the screen that was previously hidden by the foreground. Collect another piece of the Gilded Skull from it.
Continue along the path and stop before the gray platform. on the lower part of the screen, there is a pot containing a Quartz.
Head on up towards the lever and use it to bring down the big platform to climb on. Climb and head over to the top-most lever on the right. Heading back will cause you to fall down onto the now safe gray platform. Head right once and break the pot near you for another Quartz.
Head up and hit the next lever to complete your final stretch to the sections exit.