1- Zakat is not obligatory on diamonds; however, if diamonds are intended for trade, then zakat will be obligatory on those diamonds.
2- If gold or silver prevail in diamond jewellery, then they will be subject to the order of gold, and according to the conditions, zakat will be obligatory on that jewellery, and if gold or silver do not prevail, they will be in order of goods.
دلائل:
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References:
ولا زکاۃ فی الجواہر واللاٰلی إلا أن یتملکہا بنیۃ التجارۃ".
(مراقی الفلاح ۳۹۱، تبیین الحقائق ۲؍۲۳، طحطاوی ۷۱۸، المبسوط السرخسی ۲؍۳۷)
ALLAH Almighty knows best
DARULIFTA AL-IKHLAS, Karachi
واللہ تعالٰی اعلم بالصواب
دارالافتاء الاخلاص، کراچی