All praise is due to Allah, and may peace and blessings be upon the Messenger of Allah.
Originally, Qanqana refers to identifying the locations of underground water. Copper rods and other tools have subsequently been used for various purposes, such as searching for minerals and water.
As for using these rods to detect magic or jinn possession, we know of no established method or evidence proving the reliability of their results, nor do we know of any trustworthy explanation for their movements in this particular field.
The fact that a person maintains their prayers and remembrance of Allah and does not seek help from the jinn does not necessarily mean that this method is sound. The movement of the rod may be a means through which Satan misleads a person, causing them to believe something for which there is no evidence.
It is authentically reported that the Prophet ﷺ said:
"Indeed, incantations, amulets, and love charms are forms of shirk."
Narrated by Abu Dawud and Ahmad, and authenticated by Al-Albani. What is prohibited here refers to incantations involving shirk and those containing forbidden elements.
Therefore, there is a concern that using these rods to detect magic may be among the practices that open the door to illusions and attachment to matters for which there is no evidence.
The advice is as follows:
Avoid using copper rods to detect magic and jinn possession.
Do not accuse anyone of practicing magic based on the results of this method.
Direct people toward the prescribed Islamic ruqyah established in the Quran and Sunnah.
Maintain the obligatory prayers, the morning and evening remembrances, and all other prescribed forms of remembrance.
It is better to stay away from this method and limit oneself to the ruqyah and remembrances established in Islamic teachings, without resorting to unknown practices that may mislead people.
And Allah knows best