5. For gold and silver there is no exempt “gap” (waqṣ) in the calculation of zakāt; every fraction is assessed precisely. Once the amount of currency reaches its nisab, zakāt becomes obligatory, and anything above that is charged proportionally, whether the surplus is small or large. Al-Nawawī and others have transmitted the unanimous agreement of the Muslims that zakāt is due on whatever exceeds the nisab, on the strength of the prophetic reports.

6. The completion of a full lunar year (ḥawl) over the nisab is a pre-condition for zakāt; no zakāt is due until an entire year has elapsed. Al-Wazīr (Ibn Hubayrah) said: “They are unanimous that newly-acquired wealth is not subject to zakāt until a year has passed over it.”

7. As for the offspring of pastured livestock and the profits of trade, their year is counted with that of the principal capital, even if the offspring or the profit has not itself reached a nisab. This is the position of the four Imams and others.

Benefit
Wealth, with respect to the passage of the year, falls into three categories:

1. Offspring of livestock and profits from trade: their year is that of their source, even if the profit or offspring does not reach a nisab or a full year on its own.
2. Newly-acquired wealth of the same type already in one’s possession, yet not generated from it as offspring or profit: it is added to what one already owns. If the original amount was below the nisab and the new addition completes it, the two share a single year; but if the original amount had already formed a complete nisab before the second amount was obtained, each amount has its own separate year.
3. Newly-acquired wealth of a different type from what one already owns: no zakāt is due on it until a year passes over it, and it is not combined with existing wealth to complete the nisab—except in the case of gold and silver.