How to tell if metol (in powder form) has gone bad

I have a jar of metol (powder) that I bought about three years ago to use in making D-23. Haven't mixed any D-23 recently, but when I looked at the jar of metol today, I noticed the color had changed. It's gone from white to light brown. Does this color change mean it's no longer any good?

If the Metol powder is only light brown, it should work fine. Of course, the test would be to mix some D-23 and develop a small piece of film (leader or the like) in daylight to see if the developer is active. Since Metol is the only developing agent in D-23, this should tell the tale. The test would be even better if you had previously done the test and had a benchmark for developing in fresh developer. I'd bet your Metol is good; mine is the color of light sand and it works just fine.

Doremus

Light brown/tan should be fine.
You may want to reconsider how you store it if it shifted much in color within 2-3 years.

This came up a while back too and iirc, the chemists said that light gray (and pink???) are also ok.

If it's inky blue/black, it's bad...

Steve K

Mine is stored in glass at a relatively constant 72deg. It is barely light tan.

Thanks, everyone. I’ll go ahead and mix up a batch.