A jade bookmark is a thin slab cut from a larger block and polished flat. Because nephrite is unusually tough for a stone, a plaque only three millimetres thick will flex slightly rather than snap — but the drilled hole at the top is the weak point, so it should not be hung from anything that could swing.
The face is polished and the edges left marginally rough so it holds a page. Comes strung with a silk tassel, which can be removed if you prefer to use it plain.