The Mufti Ash-Shaykh Abdul-Azeez Aali-Shaykh, hafidaho-Allah, said:

“… For selling gold two conditions should be met

  1. first, immediate exchange;
  2. second, equality.
    • This means that if gold is sold for gold, the two items should be of equal quantities. But if gold is sold for anything other than gold, such as silver or currency, the payment must take place on the spot. The Prophet (peace be upon him) said: If these types differ, sell as you wish if payment is made hand to hand. Accordingly, it is not permissible for you to sell pieces of gold except on the basis of immediate payment. You should not sell gold on deferred payment or take some of the price and delay the remainder.”

[Reference]

Mentioned by

AbdulFattaah Bin Uthman
Abu Fajr