[The Ruling on Lost Property in the Sacred Precinct]

Answer: If a man finds lost property in Makkah, it is required that he announce it. If he loses hope of finding its owner, he should spend it on (public) interests. If he is poor, or there is some (personal) benefit in that, it is permissible for him to spend it on himself.
If the lost property is a small, insignificant amount, he may pick it up and spend it immediately; this is because, due to the large number of people in Makkah in this age, one quickly loses hope of finding the owner. The same applies if the lost property is scattered coins with no container and no tie, and it is found in a place where it is not possible to identify its owner. But if it is in a place where the owner can be identified – such as if he finds it in a residential building or in a private camp – then he can ask the residents of the building or the camp.
If he announces it among the residents of the building or the camp, and no claimant appears, then once he has lost hope it is permissible for him to spend it on himself if he is poor or if there is a (legitimate) benefit, or to spend it on a poor person or a (public) interest.
If a man finds money in one of the bathhouses of the Sacred Precinct, then if he wishes to pick it up, he may do so and stand by the bathhouse until its owner comes; for its owner will return to the bathhouse if he remembers it. And if he wishes to leave it, he may leave it; it is not obligatory upon him to pick it up.
On the basis of what we have mentioned, Makkah and other places are the same in the rulings of lost property. As for the ḥadīth: “Its lost property is not permissible except for one who announces it,” this – and Allah knows best – is only to draw attention to the extra sanctity of (Makkah). Otherwise, lost property is not permissible except for one who announces it, in Makkah and elsewhere. It is only that the burden of sins is multiplied in Makkah more than in other places, just as the reward of acts of obedience is multiplied there.
It is not permissible to take lost property for oneself, neither in Makkah nor elsewhere; whoever takes it for himself is liable for it.
The scholars of the madhhab have said, as in the marginal notes on Sharḥ al-Azhār: It is not obligatory to publicly announce coins (dirhams) unless proof (bayyinah) regarding them is possible – such as when they are in a tied purse. End of quote.
And they said: When one thinks the owner does not exist, the obligation of making an announcement falls from him. End of quote.
And they said: If, from the outset, it is known that the owner will definitely never be known, then it is not obligatory to seek him; this applies to hidden things such as coins and the like, and it is permissible to dispose of them immediately. End of quote.
I say: The scholars of the madhhab have said that it is not permissible to return lost property except with (proper legal) proof, and that mere mention of descriptive signs is not sufficient for returning it, even if there is a strong presumption of truth. There are, however, two other opinions:
First: that returning it based on a (correct) identifying sign is permissible, but not obligatory.
Second: that returning it based on a (correct) identifying sign is obligatory.
What is more likely to me is that it is obligatory to return it based on a (correct) identifying sign when mentioning that sign produces a strong presumption (of truth), for acting upon presumption is obligatory. On that basis, it is obligatory to make an announcement about coins even if they are not in a purse, because their owner may be able to mention (distinguishing) signs.
Furthermore, the presumption arising from mentioning an identifying sign may be stronger than the presumption produced by (formal) proof.
If it is said: Formal legal proof (bayyinah) has come to be acted upon in wealth and rights and other matters, whereas mention of identifying signs has not been established by any evidence to be acted upon – so where is the proof for acting upon it?
We say: Mentioning an identifying sign is itself a kind of legal proof, not less in its ability to produce a presumption (of truth) than the testimony of two witnesses. What is meant by “bayyinah” is anything by which the right becomes clear. They have said that it is permissible to consume the property of another if circumstantial indicators show that it has been made permissible; and they have said that if a husband and wife both lay claim to what is contained in their house, it is judged that each owns what is appropriate for him or her, with no evidence except circumstantial indication. There are many similar examples.

Source: Min Thimār al-ʿIlm wa al-Ḥikmah vol.2