Abu Dawud

Lexical Explanation:
«اَوْضَاحًا» “Dhad” with a majmah and “Ha” muhmala, is the plural of “wadhah.” Wadhah means anklet, that is, an ornament for the foot.
«اَكَنُزٌهُوَ ؟» In this, there is a hamzah istifhamiyyah, meaning it was asked whether this falls under the definition of “kanz” (hoarded wealth) regarding which there is a severe warning in the Noble Qur’an:
«وَالَّذِينَ يَكْنِزُونَ الذَّهَبَ وَالْفِضَّةَ وَلَا يُنفِقُونَهَا فِي سَبِيلِ اللَّهِ فَبَشِّرْهُم بِعَذَابٍ أَلِيمٍ ‎ ● ‏ يَوْمَ يُحْمَىٰ عَلَيْهَا فِي نَارِ جَهَنَّمَ فَتُكْوَىٰ بِهَا جِبَاهُهُمْ وَجُنُوبُهُمْ وَظُهُورُهُمْ ۖ هَٰذَا مَا كَنَزْتُمْ لِأَنفُسِكُمْ فَذُوقُوا مَا كُنتُمْ تَكْنِزُونَ» [9-التوبة:34]
“And those who hoard gold and silver and do not spend it in the way of Allah, give them tidings of a painful punishment. On the Day when it will be heated in the fire of Hell and their foreheads, their flanks, and their backs will be branded with it. (It will be said,) ‘This is what you hoarded for yourselves, so taste what you used to hoard.’”
«اِذَا اَدَّيْتِ زَكَاتَهُ» From this, the obligation of zakat on jewelry is understood. And in Sunan Abu Dawud, it is mentioned that when wealth reaches the nisab (minimum threshold for zakat) and its zakat is paid, then it is no longer considered “kanz.” From this, it is understood that the nisab is considered for jewelry. When the value of the jewelry is less than the nisab of zakat, then zakat is not obligatory on it.

Benefit:
The aforementioned narration has been declared weak in its chain by the esteemed researcher, while other scholars have considered it hasan (good) due to supporting evidences. Shaykh al-Albani rahimahullah has discussed this in detail and declared it hasan. From his detailed discussion, it appears to be the stronger opinion that this narration, due to supporting evidences, is actionable and a valid proof. For further details, see: [السلسلة الصحيحة للالباني ، رقم : 559 وصحيح سنن ابي داواد ، مفصل رقم : 1397]
Therefore, from this hadith it is understood that zakat is obligatory on jewelry used for adornment as well, if it reaches the nisab. In support of this, there is a hadith narrated from Aisha radi Allahu anha, which the esteemed researcher has also declared authentic in its chain. Aisha radi Allahu anha states that the Messenger of Allah sallallahu alayhi wa sallam saw thick silver rings on my hands, so he sallallahu alayhi wa sallam asked: “Aisha! What is this?” I replied: “I have worn them for your adornment.” He sallallahu alayhi wa sallam asked: “Do you give zakat on them?” I said: “No,” or something similar. So he sallallahu alayhi wa sallam said: “It is sufficient for you to take you to Hell.” [سنن ابي داود ، الزكاة ، باب الكنز ماهو ؟ وزكاة الحلي ، حديث : 1565]
From both of these ahadith, it is understood that zakat is obligatory on jewelry used for adornment as well, provided it reaches the nisab. «والله اعلم»