Ruling 1844 — The One-Fifth Tax (Khums)

If a child extracts a mineral, finds a treasure trove, or brings out gems from the sea by diving, his guardian must pay khums on them; and in the event that he does not, the child must pay the khums after he becomes bāligh. Similarly, if the child has lawful property mixed with unlawful property, the guardian must act according to the rules mentioned in the section on lawful property that has become mixed with unlawful property.[2]