The zodiac coin (Sagittarius) can be found whilst interacting with the Sagittarius portal, which is in the western area of the Dagon Overlook level of The Source, in the Infernal Source dig site. Finding it yields 100 Archaeology experience. It is used to access the gargoyle (Calcabrina) as part of the ramblings of a gargoyle Zamorakian Archaeology story sequence, for progress towards the Contract Claws mystery.
In order to reach the gargoyle, the player must activate any overhead protect or deflect prayer or curse before stepping through the portal.
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