Compared to anhydrite, talc reacts more slowly. While anhydrite has reached its stationary range after 2 minutes, an increase in the ion concentration can still be seen in talc after 24 hours. The reaction rate for talc increases with higher acid concentration. The leaching of both calcium and magnesium ions can be described using equation (6). The value 𝑘 Mg,i shows here a disproportionately increase in rate with the amount of acid. For anhydrite the rate is independent of the amount of acid.