The original text here in Alma 15:16 repeats the determiner his before each noun phrase in the conjunctive construction “all his gold and his silver and his precious things”. The 1837 edition accidentally omitted the second his, which creates a sequence of his-NULL-his for these three conjuncts. Elsewhere the text usually repeats the determiner or the preposition for the sequence “ gold and silver and (all) precious things”:
On the other hand, there are a couple of examples where the repetition does not occur for silver, perhaps because gold and silver are semantically linked to each other as means of exchange (and specifically described as such in Alma 11:5–19):
The critical text will therefore follow the earliest reading for each case of “ gold and silver and (all) precious things”. Here in Alma 15:16, the repeated his before silver will be restored in the critical text. For further discussion, see under Jacob 2:12; also see the general discussion under conjunctive repetition in volume 3.
Summary: In accord with the earliest textual sources, restore in Alma 15:16 the repeated his before silver in “all his gold and his silver and his precious things”.