June 2021 – Alum crystal on dinosaur

The mineral of the month was created at home. An alum crystal growth on a small dinosaur. Nina Holler did this experiment and the result looks very nice!

Alum [KAl(SO4)2 – 12 H2O]: Alum crystals can grow from a supersaturated solution, as the solubility of aluminum potassium sulfate increases with the increase in temperature.

Use: In the past, aluminum potassium sulfate was used in tanning and dyeing. Nowadays it is used in cosmetics (e.g. as a shaving stone (to stop bleeding), deodorant). 

By the way: You can also observe live experiments in our museum. Here you can see how an alum crystal grows from a supersaturated solution. You can also carry out crystal growing experiments with alum yourself at home. Just ask us the next time you visit the museum!