After I managed to find some in good condition after not being able to find any for quite some time, I'm storing mine in a super dark glass jar filled with argon and wrapped in aluminum foil to be certain no light is getting in. I had a bit that was beige in color, and after maybe 4 months it turned dark purple after being stored in the same glass jar. I added the argon by putting it in a much larger container, and filling that with argon from wine preserver. I let it sit to hopefully let all the air rise out of it, and then sealed the jar. I hope this will do the trick.