Complex sentence: The nisab of other kinds of money and currency is to be scaled to that of gold; the nisab of money is equivalent to the price of 85 grams of 999-type (pure) gold, on the day in which Zakat is paid.
Split into simpler sentences: The nisab of other kinds of money and currency is to be scaled to that of gold, 85 grams of pure gold. This means that the nisab of money is the price of 85 grams of 999-type (pure) gold, on the day in which Zakat is paid.