What is the ruling on praying next to a person wearing a coat made of pigskin, and does this affect the validity of the prayer or invalidate it if clothes rub against each other or skin touches?

It is not permissible to wear pigskin because it is inherently impure (najis al-ayn), and tanning does not purify it. Whoever prays while wearing something made of pigskin, their prayer is invalid due to the obligation of removing impurity from clothing. However, if someone prays next to a person wearing dry pigskin, and neither of them is wet, then their prayer is valid, because dry impurity does not transfer.