Is it permissible to sell manufactured carpets and rugs that contain an unknown quantity of gold for an agreed-upon price, with the possibility of profit or loss for the buyer, and is this sale considered a sale of "ghabn" (gross deception/fraudulent sale)?

It is not permissible to sell gold or any other item except after knowing its quantity and the specifications that affect its price, due to the Prophet’s (peace be upon him) prohibition of gharar (uncertainty) in sales. This is a fundamental principle in transactions. Minor gharar that cannot be avoided is excused, but significant gharar invalidates the sale. In this case, the quantity of gold should be determined as much as possible. If a slight uncertainty remains that does not expose the buyer to significant risk, then there is no harm.