What is the ruling on archaeological treasures found in land owned by ancestors, and how should they be dealt with?

The Kanz (treasure) is what was buried by people of Islam or pre-Islamic ignorance (Jahiliyyah), while Rikaz (buried treasure) is specifically what was buried by people of Jahiliyyah. Each is identified by its signs. If the land belongs to you, then if the treasure is from the buried items of the people of Jahiliyyah, one-fifth of it is due (as khums). This one-fifth is distributed like spoils of war, and the remaining four-fifths are taken by the heirs. However, if it is from the buried items of the people of Islam, it is considered a lost item (Luqatah), and it must be announced for a year. If its owner is found, it is returned to him; otherwise, it belongs to the one who found it, with the condition that it must be paid to the owner whenever he appears.