Is loss in a project with mixed capital (lawful and unlawful) considered a purification of unlawful money, or must one donate what was acquired unlawfully?

The money a person loses due to a project's failure does not absolve them from the obligation to return what they took from public funds. Rather, it remains a debt upon them, and it must be returned to the entity from which it was taken. It is not permissible to give this money as charity as long as it is possible to return it to its rightful owners directly or through an intermediary, for the Prophet (peace be upon him) said: "Upon the hand is what it has taken until it returns it." In the event that unlawful money mixes with lawful money, the unlawful portion must be extracted. If the money taken was unlawful (e.g., usury or taken unjustly), it must be returned to its owner; if the owner cannot be found, it should be given as charity on their behalf. If the matter is unclear and the amount of unlawful money is unknown, one should estimate the amount that must be returned and give it as charity on behalf of the one wronged.