C283 Question

What is this?

Lin Xiao frowned and pinched the brooch to take a look. This thing should be a material similar to platinum. How could there be black stuff inside?

She held the brooch and shook it in front of her eyes. When she heard the sound of something jumping inside, Lin Xiao frowned and pulled open the drawer to take out a black hair clip.

Because the back of the brooch was hollow