Ammonia treated gold foil is also known as:

To make gold pellets, a piece of foil is placed in the palm and each end is folded towards the center.  This incompletely formed pellet is transferred between thumb and index finger to form pellet. Rolled pellets can be stored in a gold foil box with cotton dipped in 18% ammonia (to prevent the formation of oxide layer on the pellets). Nisha Garg, Amit Garg. Textbook of Operative Dentistry.  Edition 3. Page: 373