Art Clay World, USA carries a liver of sulfur gel that has no
shelf life. It stays potent forever, and can be used full strength
at room temperature, or diluted in hot water. artclayworld.com.
I’ll second that. The gel form is new (this year), and is advertised
as having a much better shelf life. It’s available at many of the
jewelry tools suppliers, though not yet in most catalogs (since it’s
new). Frei and Borel has it, so does Allcraft, and I’d assume Rio,
Gesswein, and the others have it too. The smaller sized jar in
particular (which likely will still be enough to last many people for
years) is a lot cheaper than the usual sized can of the liver of
sulphur chunks. And being already in gel/liquid form, it’s quicker
and easier to use. Mixes in water quickly without needing to be
heated if you want more dilute than the full strength gel (which is
probably stronger than you want, and less useful for dipping a whole
piece.) Even the mixed solutions seem to last a bit longer than mixed
solutions of the chunk variety of LOS.
For me, despite being careful to close the cans well, no matter what
I do, they always end up degrading in a couple years. Even brand new,
never opened cans have turned out useless after a few years storage.
How long the stuff lasts may be related to the humidity levels of
where you live. Don’t know. But here in Seattle at least, and prior
to that, in Detroit, the usual form of LOS does not have a good shelf
life no matter what I’ve tried. Paying twenty five bucks (or
thereabouts) for a can of the stuff and ending up getting use out of
only ten percent of the can before it’s degraded is annoying to say
the least. Keeping the chunks as large as possible helps because they
degrade from the outside in, and an older container that’s mostly
worthless may still have some larger chunks which, when split, will
still have a bit of the active dark brown LOS in the middle. The
outer light green degraded material does not interfere with the
action of the solution you mix, if there was still some of the dark
brown material in there, but the latter is the only part of the
chemical that’s doing the work.
So thanks to the developers of the Gel form. Let’s hope the shelf
life is as good as they claim it will be.