GATHERING
SEIF 9
The Gemara says that if someone gathers salt from the place where saltwater is dried during the salt-making process, Rabba says he is Chayiv for the Malacha of Maamar (gathering). Abaya says that one would not be Chayiv for Maamar since this Malacha applies only to substances which grow from the ground. The Rambam and Rosh Paskin like Abaya. Still, the Tur says gathering from a substance which does not grow from the ground is prohibited MiDirabanan.
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