When my uncle was teenager, he decided he wanted to put a firecracker in a glass coke bottle to watch it explode. He lit the firecracker, dropped it in the bottle, stepped back a few paces, and at the last second realized that actually watching the event was not a good idea. He turned his back just in time.
The hospital got the biggest shards out of the back of his head, but little pieces got pushed out (by the wonder of skin) over the next few decades.
When my uncle was teenager, he decided he wanted to put a firecracker in a glass coke bottle to watch it explode. He lit the firecracker, dropped it in the bottle, stepped back a few paces, and at the last second realized that actually watching the event was not a good idea. He turned his back just in time.
The hospital got the biggest shards out of the back of his head, but little pieces got pushed out (by the wonder of skin) over the next few decades.