From The Grey House:
The Slayer took it tentatively, not liking the odd, unidentifiable look on her face. Thinking it would help, he gathered the necklace in his fist and threw it as far as he could. The look seemed to intensify. Confused, Zechariah shook his head and bent down to grab her clothing. The belt clinked again, and Natalia remembered the coins. Her expression changed slightly, but not enough to arouse suspicion.
“There’s some change in the pocket of those jeans.”
Zechariah continued to ball up the clothing. Dean brought over a plastic bag. “All of this is from your past. You don’t need any of it.”
Natalia held her tongue, knowing she couldn’t say anything more. Whatever the coins really were, she had lost them. She hoped they weren’t as important as she felt they were.