Aveidos at the beach
If one saw that someone’s coin or ring fell into the sand or dirt, he may take it if he finds it, as the owner certainly gave up on finding it. Even if he sees him bring a sieve to sift through the sand or dirt for the item, the finder does not have to be concerned (שו"ע חו"מ רס"ב סי"). The reason is that sifting through the sand for an item does not show that a person did not give up on it; he just thinks he might at least find someone else’s (סמ"ע שם סקכ").
However, other items in the sand that appear to have been forgotten there are not subject to the above heter. If one picks them up, he must publicize them like any other aveida.
One may not hand over an aveida he finds to the lifeguard chair if the lifeguard is not observant; that is considered negligence in safeguarding the item (מבואר משו"ע הגר"ז סכ"). One must put up a sign at the spot he found the item.
