You cannot directly post them in chat since the game does not support GPS-like geolocation (players don't have direct access to these coordinates within the game interface). However, you can use the third-party tool TibiaMaps.io to create a link with the coordinates, which you can share (simple and effective workaround).
Go to the interactive map on TibiaMaps.io/map; Navigate to the desired location you want to share (the link in the address bar will automatically update with those coordinates); Copy the updated link from the address bar and paste it into the chat to share it with others.
For example, the link for Asura Palace would look like this:
https://tibiamaps.io/map#32949,32691,7:2
The link contains specific map settings after the hashtag (#) symbol. Here's how to interpret the link (you don’t really need to know this, but it can be handy if the link doesn’t update automatically):
- First number (32949): East-west coordinate (X).
- Second number (32691): North-south coordinate (Y).
- Third number (7): Floor level, where 7 usually represents ground level.
- Final number (2): Zoom level for the map.