Sending Gem

Wondrous item, rare (requires attunement)

This finely-cut, clear, ovoid gem fits easily in the palm of the hand; when you attune to it, it takes on a faint blue glow. While holding the gem, you can use a bonus action to call upon its stored magic to cast sending, targeting any number of other sending gems known to you. When a sending gem receives a message, it flashes a brighter blue and vibrates. To send your message through the gem, you must speak into it. Similarly, to receive a message, the gem must be held to your ear. Each sending gem can send an unlimited number of messages. Sending gems cannot send messages to creatures who do not themselves possess sending gems.