Jessica found it laying in the field behind her house. She was sun bathing nude when, in the corner of her eye, she saw something glittering in the sunlight.

It was a golden pendant. When she wore it, she saw her body disappear. Jessica wasn't hurt in any way, but she was just invisible. She took it off.

She went back inside, put on some clothes, and put the pendant back on. Jessica's body disappeared again but her clothed stayed visible.

She would have to be naked to be invisible.