Long range communication?

Adding a crystal that can be used once for temporary long range communication w/ friends

Core concept
Exploring deeper levels in the mines (perhaps the crystal layers?) gives the player a chance to find a crystal that can be used for a short time to talk to their friends from long distances as long as they have a crystal as well (like a telephone but more period appropriate). Once the time is up the crystal will break and be destroyed.

Personal twist (optional)
1.When someone attempts to “call” their friend a humming noise will be heard. Once the player holds the crystal they will start to hear their friends voice.

2.Make it so that you cannot stack this item so that people can’t just horde it (kind of like carrying a bottle)

3.The audio source will come from the crystal itself (This is so that it doesn’t break immersion). Holding the crystal closer to your head will make the voice louder.

Already got a post that is very similar to this. Telecommunications Bracelet