For example, if a person possesses one-third of a silver nisab, one-third of a gold nisab, and trade goods which, if assessed in silver, amount to one-third of a nisab, but, if assessed in gold, do not amount to one-third of a nisab, should their value be assessed in gold or in silver?
The answer is that the scholars have said: trade goods are assessed according to whichever is more advantageous to the poor. Thus, if they complete the nisab when assessed in silver but not when assessed in gold, they are assessed in silver; and if they complete a gold nisab but not a silver nisab, they are assessed in gold.
What they have held regarding adding the value of trade goods to gold and silver is correct, and this is done in the manner more advantageous to the poor.
Issue: If we say that the gold nisab is combined with silver, and that the value of trade goods is combined with either silver or gold, must zakah be paid from each type, or may it be paid from only one of them?
The answer is that, according to the established position of the school, zakah must be paid from each type itself: gold is paid from the gold and silver from the silver, because the hadith states, “One-quarter of one-tenth is due on silver currency” (1)—that is, from silver.
And the hadith concerning gold states, “Half a dinar” (2)—that is, from gold.
Thus, zakah is due from each type itself, just as they say regarding grains and fruits: it is paid from each variety.
The correct view, however, is that there is no harm in paying from one of the two types—that is, according to its value.