Is the price of gold written in the deferred dowry calculated at its value at the time of divorce, or at its value today, at the time of completing the official procedures?

There is no objection to the deferred mahr (dowry) being gold. If it becomes due upon divorce, it is obligatory to pay it unless the wife waives it, because it is a debt owed by the husband. Therefore, either the agreed-upon gold is paid as is, or its value at the time of payment is given. The considered value should be its value on the day of payment, not on the day of divorce or contract, based on the hadith (definition) of Ibn 'Umar (may Allah be pleased with them both): "There is no harm in it, if it is at the price of its day, and you do not separate while there is anything between you."