Is zakat obligatory on inherited antique silver artifacts, and what is their nisab in grams? If zakat is due for past years, should it be calculated based on the current year's price or the previous year's?

Possessions that are containers and contain silver are subject to zakat if the silver reaches the nisab (595 grams). The silver must be removed from them, and it is forbidden to use them as long as they contain it. If the silver does not reach the nisab, there is no zakat on it.

A quarter of a tenth (2.5%) of the silver's value must be paid in cash for each year that has passed, with the valuation based on the current price of silver.

As for possessions that are jewelry worn by women, there is no zakat on them according to the majority of scholars.