Plant hormone rooting powder (Hatfield AL10)

It's an artificial version of a natural plants hormone they make themselves. You dip the root-end of cut stems in when taking cuttings and it's supposed to make them root much faster/more easily.

I use it sometimes, but I have another pot - this one was acquired from my Gran's house.
For rooting plants in compost or soil, not water - because the powder would just wash off the stem.

It's quite old, but I assume it lasts indefinitely.