How is Zakat calculated on jewelry intended for trade?

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If the jewelry is for trade, it is valued. If its value, when converted to gold or silver, reaches the Nisab, Zakat is due because Zakat relates to value in trade goods. The owner has the choice between paying one-fortieth of the jewelry calculated proportionally (musha') or paying the equivalent value of one-fortieth from the same category of wealth. It is permissible to pay more than one-fortieth of the weight because usury (Riba) does not apply here.