Praise be to Allah.
The basic principle with regard to bracelets is that they are permissible, because they are one of the things with which women adorn themselves, and Allaah has denounced those who forbid adornments without any shar’i evidence. Allaah says (interpretation of the meaning):
“Say (O Muhammad): ‘Who has forbidden the adornment with clothes given by Allaah, which He has produced for His slaves, and At-Tayyibaat [all kinds of Halaal (lawful) things] of food?’ Say: ‘They are, in the life of this world, for those who believe, (and) exclusively for them (believers) on the Day of Resurrection (the disbelievers will not share them).’ Thus We explain the Ayaat (Islamic laws) in detail for people who have knowledge”
So no kinds of adornment are forbidden except those for which there is proof with shar’i evidence that they are haraam. As for those for which there is no proof that they are haraam, they are halaal.
With regard to the question of whether these bracelets come under the ruling on those who wear threads, what is meant by the prohibition on wearing threads is those who wear them in order to ward off the evil eye, or to ward off a sickness for which there is no proof that these threads can bring about healing from it. Wearing them for the purpose of adornment is not included in this prohibition.
If these threads are usually worn to ward off sickness or the evil eye, then wearing them is haraam, and a woman is forbidden to wear them even if she does not intend that haraam purpose, and she only intended it as an adornment, because in that case she is still resembling those who wear them for a haraam purpose, so she exposes herself to suspicion and gossip, as people will think that she is wearing them for that haraam purpose. And there may be an even worse consequence, as other women may follow her example, especially if she is in a position of respect.
With regard to imitating the people of shirk, this is subject to further discussion. If it is one of their unique characteristics and symbols, then wearing it is haraam, because it is established in sharee’ah that it is haraam to imitate the enemies of Allaah, as the Prophet (peace and blessings of Allaah be upon him) said: “Whoever imitates a people is one of them.” Narrated by Abu Dawood, classed as saheeh by al-Albaani.
If it is proven that it involves imitating the kuffaar, then wearing it is haraam, even for those who do not wear it with any intention of imitating the kuffaar, because imitating them may happen in one’s clothing and appearance, whether one intends to resemble them or not, as was explained by Shaykh Muhammad ibn ‘Uthaymeen (may Allaah have mercy on him) in al-Qawl al-Mufeed (3/203).
With regard to examining the intention before denouncing evil, whatever is proven to be evil according to sharee’ah must be denounced, and the intention of the one who does it does not matter, because a good intention does not turn an evil deed into a good one. Evil is evil even if the person intends something good thereby.
But intention – good or bad – can turn permissible things into acts of worship or sins. If a person eats with the intention of strengthening himself for worship, this is an act of obedience and worship. If he intends thereby to strengthen himself to wrong people or commit immoral deeds, then it is a sin.
To sum up: If these necklaces and bracelets are worn with the intention of warding off the evil eye or jinn, or to bring good luck and the like, then wearing them is haraam.
Similarly it is haraam to wear them if they are unique characteristics or clothing of the kuffaar. In that case the intention of the one who wears them, and whether he intends to ward off the evil eye or not, or to imitate the kuffaar or not, does not matter.
But if he is not wearing them to ward off the evil eye, and it does not involve imitating the kuffaar, and the intention is only to adorn himself, then it is permissible.
And Allaah knows best.