Is the mortgaging of a sold item valid when its possession is stipulated (as a condition of the sale)?

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Al-Qadi mentions that mortgaging an item whose delivery (Qabd) is stipulated in the sale contract, such as measured or weighed goods, is permissible before actual delivery. This is because the right to take possession is established for the buyer, allowing the buyer to take possession and then subsequently mortgage it. Selling such an item before delivery, however, leads to profiting from something not yet guaranteed, which is prohibited.