Is zakat obligatory on a wife's gold (the dowry), and how is the zakat calculated for gold that was purchased in 2009 and is 21 karat?

Zakat is not obligatory on gold owned by a wife if it is jewelry for permissible use, even if it is not currently being used, according to the opinion of the majority of scholars. If it is said that Zakat is obligatory on it, then the wife is responsible for it, and the husband is not obliged to pay it. It is not valid for him to pay it on her behalf unless she authorizes him to do so. Therefore, there is no sin on the husband for not paying the Zakat on this gold.