I tried a while ago also to contribute something, but figured out that the materials do not look the same when using other lighting set-up´s. Therefore i did not submitted nothing yet.
Here´s one example what i mean. For my material set-up learning i use the fantastic cgsphere file from Hans. You can see on the left, how my material looks when used with Gianluca´s file. Maybe other´s encountered similiar effects, hence not much people
provided materials yet?!

Regards
Stefan
P.S. for those who viewed this already i forgot to tick the “World Map checkbox” which is now corrected in the left image. Sorry about that!