Praise be to Allah, the Lord of the Worlds; and blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions. The Nisab (the minimum of one's holdings liable to Zakah) of gold and silver is as follows: 1 - Gold : 20 Mithqal = 85 grams. 2 - Silver: 200 Dirham = 595 grams. As for your own holdings, they do not constitute the Nisab unless they are combined. So, you are to combine them, value them and then to pay 2.5% as Zakah of the total value. But, if the gold or silver reaches the Nisab, then you have to pay the Zakah of each kind separately. As to combining gold and silver, Imam al-Shafi’e and others believe that combining should not be done as long as we have two different kinds and none has reached a Nisab. On the other hand, according to the Majority of Muslims scholars, if the gold possessed is not equal to the value of 85 grams, or the silver possessed is not equal to the value of 595 grams, but the value of both combined is equal to the value of either the Nisab of gold or siver, then Zakah becomes obligatory, taking the interest of the poor into consideration while calculating the rate. Allah knows best.