What is the ruling on selling silver online in the manner described, where an agreement to sell is made before the seller possesses the commodity, and the price is transferred as a trust until the buyer receives the silver?

The sale of gold and silver requires immediate possession (taqabud) at the time of the contract. In the presented transaction, if the transferred amount is a trust (amanah), and both parties are not obligated to sell or buy, then each has the right to withdraw from the promise. The price is agreed upon when the sale contract is concluded after the goods arrive, and the transferred amount then becomes the price.