As said in my comment you may have confused the name of the mounts.
The prophet () lived most of his life in Mecca and had most of his opponents (more explicitly the disbelievers among them and idolaters) in Mecca. In Medina he mainly had two kinds of opponents the Jews and the hypocrites. So it sounded rather irrational that this incident happened in Medina. And therefore I turned away from searching about incidents quoting the mount Uhud (which is close to Medina) to those quoting mounts close to Mecca.
In Tafsir ibn Kathir you may find the following quote:
The Reason why Allah did not send Signs or Miracles
Sa'id bin Jubayr said, "The idolators said: "O Muhammad, you claim that before you there were Prophets, among whom was one to whom the wind was subjugated, and another who could bring the dead back to life. If you want us to believe in you, ask your Lord to turn As-Safa' into gold for us." Allah conveyed to him by inspiration (Wahy): "I have heard what they have said. If you wish, I will do what they say, but if they do not believe after that, the punishment will come down upon them, because after the sign has been sent, there is no room for speculation. Or if you wish, I will be patient with your people and give them more time.' He said:
(O Lord, give them more time.)"3
This was also narrated by Qatadah, Ibn Jurayj and others.
Imam Ahmad 1 recorded that Ibn 'Abbas said, "The people of Makkah asked the Prophet to turn As-Safa' into gold for them, and to remove the mountains (from around Makkah) so that they could cultivate the land. It was said to him (by Allah): "If you wish, I will be patient and give them more time, or if you wish, I will do what they are asking, but if they then disbelieve, they will be destroyed as the nations before them were destroyed." He said,
(No, be patient and give them more time.) Then Allah revealed:
(And nothing stops Us from sending the Ayat but that the people of old denied them. 17:59 )
An-Nasa'i (+) also reported this from the Hadith of Jarir.
Imam Ahmad 2 recorded that Ibn 'Abbas said: The Quraysh said to the Prophet , "Ask your Lord to turn As-Safa' into gold and we will believe in you." He said,
(Will you really do that) They said, "Yes." So he asked his Lord, and Jibril came to him and said: "Your Lord conveys His Salam to you and says, "If you wish, I will turn As-Safa' into gold for them, then whoever of them disbelieves after that, will be punished with a torment the like of which has never be seen in creation; or if you wish, I will open the gates of repentance and mercy for them."" (Source qtafsir for verse 17:59)
So the mount which the opponents of our prophet () asked to turn to gold was as-Safa.
1 At least ibn Kathir considered this narration to be good and having a witness in his al-Bidaya wa an-Nihayah. Al-Hakim commented this that it is a Sahih narration, but was not compiled by neither the two sheikhs. All the narrators are rather trustworthy as far as I can tell after checking the version of imam Ahmad.
2 Appears in al-Albani's sahih al-Musnad with an indication that it is sahih.
3 There's a similar narration in al-Mustadrak of which al-Hkaim says that it meets the conditions of Muslim, but it is about repentance and mercy not time!
Note that the ahadith quoted by imam ibn Kathir here also appear in al-Mustadrak of al-Hakim from Nishapure and an-Nasa-i's quote (+) seems to appear in his as-Sunan al-Kubra.