Short answer
No. The mangalsutra and sindoor are marriage symbols from Hindu religious practice, given with wedding rites and prayers, so wearing them imitates another faith's religious symbols, which is haram. A Muslim wife may wear any ordinary jewellery, including gold chains and plain black-bead necklaces where they carry no religious meaning. The four schools agree on the principle.
Wearing a symbol that belongs to another religion is haram, and graver when done with that religion's meaning in mind. Ordinary jewellery with no religious significance is permitted for women.
The four schools agree on this.
Explanation
The Prophet ﷺ said that whoever imitates a people is one of them. The Hanafi scholars apply this most strictly to religious symbols: a cross, a sacred thread, or anything a community wears as part of its worship. These are not allowed for a Muslim; see imitating non-Muslims in clothing.
The mangalsutra and sindoor. In Hindu tradition the mangalsutra is tied by the groom during the wedding rites, often with mantras, and is seen as a sacred sign of a married woman. Sindoor in the hair parting carries a similar religious meaning. So a Muslim woman should not wear either, even if relatives or neighbours expect it.
Ordinary jewellery is fine. A Muslim wife may wear gold chains, pendants, bangles and nose rings as adornment. In some Muslim communities a black-bead necklace is worn simply as jewellery. Where it carries no Hindu meaning among the people around you, many muftis allow it, but if people would see it as a mangalsutra, leave it so your identity stays clear. If a local custom is unclear, ask a mufti who knows your area.
Bindi. A bindi worn as a religious mark takes the same ruling as sindoor. A purely decorative forehead jewel is a cultural matter, but because of the confusion many scholars advise leaving it.
In Islam a marriage is complete with the nikah and the mahr; no necklace or ring is needed. See the nikah guide and do Muslims wear wedding rings.
The evidence
Quran, Surah Al-Kaafiroon 109:6
لَكُمْ دِينُكُمْ وَلِىَ دِينِ ﴿٦﴾
For you is your religion, and for me is my religion."
A Muslim keeps the signs of their own faith distinct from other religions.
Sunan Abi Dawud 4031
Graded hasan sahih... من تشبه بقوم فهو منهم ...
"Whoever imitates a people is one of them."
The basis for avoiding other religions' symbols.
Where the ruling is recorded
- Radd al-Muhtar (Ibn Abidin), Kitab al-Hazr wa al-Ibaha. Imitation is blameworthy when it is in what is particular to another people, especially their religion.
- al-Fatawa al-Hindiyya, Kitab al-Siyar, chapter on the rulings of apostates. Wearing the distinctive religious items of another faith without need is a grave matter.
Checked by our team. For a more accurate answer to your own situation, consult a scholar. Quran translation by Sahih International. Hadith Arabic from the standard editions of the six books and the Muwatta, with gradings as recorded there; the English is our own rendering. Spotted a mistake? Tell us.