This relates to Shabbos 142a, where the Gemara discusses the words from

the mishna ''kalkala vehaeven besocha.''

The Gemara rejected the idea of dumping the fruits on the floor since they would become ruined. The Gem. then asked, let him shake the basket so that the stone falls out, leaving the produce behind. The Gemara's answer was that the stone became part of the basket wall.

My question is, this suggestion that he should shake the basket so that

only the stone falls out would seem to present a problem of Borrar, since he is, in effect, removing the stone (i.e the undesired item) from the produce (i.e. desired item) Rashi (d''h ''velinaareenhu na'oorei'') says the actual separating takes place in the basket, before the stone leaves it. But the question would seem to persist anyway since, if he removed the fruits by hand from the stone, it would not be for immediate consumption. And, taking the stone from the fruit, a large mixture, seems unfeasible.

Any light you can throw on this is greatly appreciated.