The enchantment animation on armor(my example was iron armor) had a part where it was transparent, and becomes see thru..

On a set of armor, purple lights will go up and down the armor, to show that it is enchanted. When a specially bold purple line goes up, below it is a window that makes the armor transparent; showing what's behind the player's menu. I just logged in and checked my inventory( this was in a private survival game) and saw a piece of a tree on my armor. I have no mods on or have any downloaded.