Ruling on selling metal riyals for paper riyals with an increase

Question:
We move on to a letter sent by the questioner (A. A. A) from the Arab Republic of Egypt, in which he says: What is the ruling in the Shari'ah for one who sells nine halalas for ten riyals, and gives juice or anything else for the tenth riyal? May you be rewarded.

Answer:
There is disagreement among the scholars of this era, and the best course is not to increase the amount; ten for ten, and one hundred for one hundred, and so on, because they are all riyals. This is metal and this is paper, so the best is not to differentiate between them. The best is ten for ten, twenty for twenty, and thirty for thirty. This is the most cautious approach, based on the saying of the Prophet (peace and blessings be upon him): Some of our brothers among the scholars said: There is no harm in it, because metal is not paper, so there is no harm in differentiating between them, just as the riyal was sold previously... It is a matter of difference, and just as the riyal is sold for other things like iron because they are different, there is no harm, meaning: in general. However, if one is cautious regarding his religion, acts with caution, and takes the metal halalas for paper in equal amounts, ten for ten and one hundred for one hundred, this is the most cautious and furthest from doubt, based on his saying (peace and blessings be upon him): Yes.

The presenter : May Allah reward you with good, O His Eminence the Shaykh.