Is Zakat obligatory on all wealth if the threshold (nisab) is reached and a year (hawl) has passed on only half of it?

Whoever possesses the minimum amount (nisab) of money (which is equivalent to 85 grams of gold or more) and a full year has passed on it, must pay zakat on it. The questioner must pay zakat on the money that has reached the nisab as soon as a year has passed on it. As for newly acquired money that has not yet had a full year pass on it, zakat is paid on it when its own specific year is complete. It is not obligatory to pay zakat on it with the first amount of money according to the preponderant opinion, although if one were to pay zakat on it with the first amount, it would be considered valid.