I know it's been talked about but I'm going to put my 3 cents in. You pay good money for a quality backquiver and some guys let them rot away.
I've seen good quivers with enough mold on them, I was looking for mushrooms, add dirt and you have just wasted good, quality leather.
This time of year I leave my quivers on the deck in the hot sun. Get them good and warm and pliable. I then liberally apply Montana Pitch Blend and rub it in deeply. I give the entire quiver a good "coating".
Around July, I repeat this again. My John Schulz quiver was bought in 1977 and it looks new. I beat this quiver up all these years across this country and Canada. Take care of your backquivers and they will last a lifetime. Don't get lazy....Don't care what conditioner you use but use something.
Creger with a good coat of pitch blend
My Schulz after some drying time. This quiver was originally honey colored.
Side by side....
Some good stuff here...