Some commentators of the Holy Quran have reported that Allah would melt the copper as per need of Sayyiduna Sulayman and this was a distinctive feature and miracle of Sayyiduna Sulayman – No person before him knew the art of melting the metal.
(Iazkira-tul-Ambiya, pp. 377, part 22, Surah Saba, Ayah 12)
Najaar has reported that Allah rewarded Sayyiduna Sulayman by revealing to him the springs of copper that were flowing in certain parts of the earth, due to the presence of combustible fluids, which caused copper to melt and flow like water. No one before him was aware of these springs of metal underneath the surface of the earth. Hence, Ibn-e-Kaseer has reported from Qatadah that the springs of the molten copper were in Yemen, which Allah revealed to Sayyiduna Sulayman (Al-Bidayah wan-Nihayah, vol. 2, pp. 28)
However, the Holy Quran has not disclosed any such explanation that in what form these springs of copper were found by Sayyiduna Sulayman · However, the Ayah of the Holy Quran in which this miracle has been mentioned can be a verification of both the abovementioned aspects. That Ayah is as follows:
And We caused a spring of molten copper to flow for him.
[Kanz-ul-Iman (Translation of Quran)] (Part 22, Surah Saba, Ayah 12)
To have control over the wind and the springs of molten copper is among the miracles of Sayyiduna Sulayman which are proven from the Holy Quran. To believe in them is among the requisites of Islam. Some heretics who are deprived of conviction in miracles use to express baseless and lame interpretations of these miracles. It is mandatory for the Muslims to not pay heed towards these heretics and keep unshakable belief in miracles.