Archeology shards -> stick length + jewel + map room -> treasure location

In a nod to the classic Raiders of the Last Ark movie scene, how about if you find four ceramic shards in an archeology dig, you can craft them into a set of instructions. The instructions give:

• the number of sticks to combine into a staff
• the jewel type to use at the top of the staff
• the location of a nearby buried map room

The player then crafts the appropriate staff and finds the nearby map room. The map room has a map of the surrounding area on its floor. The player places the staff in a provided hole in the map room and waits until midday. At midday the sun will shine on the staff and light up a particular location on the floor of the map room telling the player where some treasure may be found.