I have written about Tigerklo covers before here. I have the limited edition natural cover which darkens with exposure to light. The leather is tanned in the same factory as Louis Vuitton leather. I have always lusted after the exclusive NK oxblood version of their natural tan A5 nipple stud cover. Recently I was lucky enough to be able to find this cover on sale at 50% off and I got the last one. It is absolutely gorgeous and was made for one store in Stockholm. At the very bottom are photographs of this same cover in oxidizing natural leather and my two natural ones at two years old.
Each of these covers comes in a paper bag to protect it from air and light until you get it. So every bit of the colour development and darkening comes completely from you and your life.
I really do love natural leather in all its phases of colour changes.
So do I!