What is the ruling on hanging wind chimes made of seashells solely for decorative purposes?

It is permissible to use bells for decoration if they do not emit melodious sounds and if there is no belief that they bring blessings. This is because the default rule for things is permissibility and lawfulness until there is evidence of prohibition, and due to Allah Almighty's saying: "He is the One Who created for you all that is in the earth." Ibn Taymiyyah stated that the early scholars did not differ on the point that whatever has no evidence prohibiting it is permissible.