The main RuneScape Wiki has an article on: Stone tablet
The Old School RuneScape Wiki also has an article on Stone tablet.

Stone tablet is a quest item found in the end of Digsite quest in the Zarosian dungeon underneath the Digsite. When the item is read it reveals that the dungeon holds the altar dedicated to zaros.

Transcript

This article on an item has an associated transcript page.

Spawn location

See also

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