question on old(ish) fix....

I have been given a gift:

19 bottles, each containing 5 liters of concentrated fix.

Nice, when you have students!!

There are two different ones, and I know them both.

about half of them are Agefix, and there's nothing wrong with those ones...

But the second half is Tetenal Superfix, (a fix I normally use) and inthose bottles, a sediment seems to have formed in the bottom of the bottles...

Is the fix unusable - can I heat up the fix, and then make the sediment "go back" to original state?

Someone must know.

I don't

Your nose should tell you : give that Tetenal a good sniff.
If a nasty sulpherous stench - it's doubtful/dead. Dilute some and test with film leader ,compared with the Agfa.
If it clears in good time I would trust it.
Filter off the clear portion.
I think it's kaput though.

I used to get Kodafix bottles that were left behind by students in a community darkroom.
I ended up with some that sat for maybe 5-6 years and had some "flakey" material that I surmise was sulphur.

Long story short, I filtered the gunk out and used it. I always did clip tests for clearing time to calm my paranoid nerves.

Bottom line, I wouldn't use it on any really serious/critical work.
I wouldn't trust the archival property.

hmm - thank you.

I have read somewhere, that if this occurs in colour bleach/fix, a heating can make it as new again...

hence my question on heating

emil

if you use a 2 bath system,
you could probably filter out the sediment
and use THAT fix as your first bath ( after your clip test )
and " good-stuff " for your second bath.