Aikon's Unlimited Sending Stone

This magical stone was created by the great wizard Aikon in an attempt to fabricate an item that would allow communication across vast distances without burning magical energy, and without the limits that other similar magic items have when it comes to charges. The result is a chunk of obsidian inset with ten gemstones, each with a different arcane rune etched upon its face, that uses the attunement of its owner to power itself. 

While attuned to this item, you can cast the Message cantrip at will. In addition, you may also cast Sending at will, removing the word count limit, to any other creature in possession of an Unlimited Sending Stone, provided you know their Stone's sigil combination. If the target of the spell is not in possession of an Unlimited Sending Stone, Sending casts as if you had cast the spell normally and your Unlimited Sending Stone becomes inert until the next dawn.

Notes: Communication, Social, Utility, Eldritch Machine, Artificer