All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
The scholars of Islam differed in opinion concerning Zakat on ornaments and jewels used by women.
According to the majority of the Muslim scholars, ornaments and jewels used by women are not subject to Zakat as long as they are not intended for trading.
The other opinion states that such ornaments and jewels are subject to Zakat as long as their value equals 85 grams of gold and one possessed them for one lunar year.
The opinion of the majority of the scholars –Allah knows best –is the more predominant one, since such wealth will not increase and it is intended for personal use.
Nonetheless, it is good if one pays Zakat on one's jewelry. However, if a woman, as mentioned by an-Nawawi in al-Majmoo' and Ibn Qudaamah in al-Mughni, keeps such jewelry as a treasure or trade, then she has to pay Zakat.
On the other hand, if a man adorns himself with a golden ring or the like, or adorns himself with silver other than a ring, then he has to pay Zakat on that ornament, since this practice is forbidden.
Finally, you may refer to books on Zakat, which is the third pillar of Islam.
Allah Knows best.