Is the niṣāb calculated based on the price of 21-karat gold, or 24-karat gold?
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah ﷺ.
Zakāh is obligatory on cash and on gold designated for saving or for trade, provided the total reaches the niṣāb (minimum threshold liable for zakah), and a full ḥawl (lunar year) has elapsed over it. The niṣāb is (85) grams of 24-karat gold; for 21-karat gold, the niṣāb equals (97) grams; and for 18-karat gold, it equals (113) grams.
The relied-upon position is to calculate the zakāh based on the buying price [i.e., the price the gold merchant would pay the owner to purchase the gold from him] on the day the zakāh obligation is due.
The one paying zakāh may assess/calculate the niṣāb using any of the aforementioned gold karats [i.e., he may choose whichever karat standard he wishes for the purpose of the calculation]. And Allah, the Exalted, knows best.
Is it permissible for a wife to give her money to her family as a charity, or a gift without asking her husband, or seeking his consent?
The wife has the right to give her money as a charity, or a gift to her family, or to other people after consulting her husband out of respect, and this is the meaning of treating on footing of kindness and equity. Therefore, if he wanted to stop her from helping her family, then there is no harm in not telling him.
Does undergoing surgery under anesthesia break the fast?
Anesthesia itself does not break the fast because anesthetic gases have no physical substance (jirm), and subcutaneous anesthesia injections do not reach the body cavity (jauf). However, this is on condition that the person is conscious at some point during the fasting hours:
● If they were awake at the beginning of the day, their fast remains valid.
● If they wake up even for a moment before sunset, their fast is also valid.
However, if the surgery involves the entry of foreign substances into the body cavity, their fast is invalidated, and they must make up for that day later.
What is the ruling on someone who possesses cash reaching the niṣāb (minimum threshold liable for zakah), and then uses part of it to purchase gold before the ḥawl (lunar year) is complete — must he pay zakāh on all of it [combined], or only on the remaining cash, excluding the gold?
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah ﷺ.
Gold acquired for hoarding and saving is subject to zakāh once it reaches the niṣāb (minimum threshold liable for Zakah) — when combined with any cash held — and once a full ḥawl (lunar year) has elapsed over it. The starting point for calculating this ḥawl is the ḥawl of the paper currency [used to purchase it], which had already reached the niṣāb and was then used to purchase the gold.
It is stated in Mughnī al-Muḥtāj (Vol.2/p.78): "As for someone who sells silver in exchange for gold, or vice versa, zakāh remains obligatory upon it, since he builds [the calculation of] its ḥawl upon [the ḥawl established at the time of] the original transaction [i.e., when the wealth was first acquired]."
This has already been explained in detail in Fatwa No.
2670 — please refer to it.
And Allah, the Exalted, knows best.