SilverWook said:
I think it's been documented that Yoda's original latex skin rotted away years ago.
There was a photo of an ILM storage area in Smithsonian Magazine in the 90's and a half rotted Yoda skin could be seen lying on a work table. Kind of a gruesome sight!
I believe you're correct. If memory serves, there's a photo in my Lucasfilm Archives book that shows the original muppet, and the latex was in pretty bad shape at the time the photograph was taken.