How is the zakat on gold and silver calculated in a shop that includes raw materials and manufactured goods displayed for sale, with a managing partner who has 50% of the profits reinvested in the project, and is the zakat calculated based on the cost price or the selling price?

Zakat is obligatory on gold and silver if they reach the nisab (minimum threshold) and a hawl (full lunar year) passes on them. The merchant then pays 2.5% of their weight when the hawl is complete, without considering their monetary value. The zakat can be paid from the gold or silver themselves, or from their value in currency. As for the agent in mudarabah (profit-sharing partnership), he does not own his share of the profit until after distribution and segregation, and he cannot consider it capital before receiving it.