Place a few drops of a 10% KOH solution on the pileus surface of fresh material. Any colour changes occur rapidly. If there is a colour change, it is often visible also on dried material.

SAFETY NOTE: KOH is corrosive at higher concentrations.

Choose this state if: the application of KOH to the pileus produces a distinct colour change, such as brown, red or purple, in contrast to the normal colour of the pileus. Choose black if the change is to that colour.

If the colour change is only a slight intensification of the original colour, choose no colour change.