Can Tandy Dye, Stain, And Super Sheen Go Off?

[lorraine g]

Hi folks. I'm new to leather work and just bought a job lot of old kit. Apart from the leather smelling musty (now in my freezer) can tandy dyes, stains and super sheen go off. Going by the paperwork in the box, the liquid stuff is at least 20 years old. Any help would be greatly appreciated. Thanks.

[billybopp]

I'd try the dyes and stains on some scrap. If it works, it works. The super sheen or other finishes, I'd replace.

Bill