Long story short: I had a Klaus fight today which was in the mosaic, and I had some meteors falling down during it. At the beginning of the fight I left some non-burnable items as reserves on the ground: helms, an amulet and my eyebrella (as it was winter's last night). I also left my backpack a bit further to protect it from any fire. After the fight I noticed that my eyebrella and my amulet disappeared. Furthermore my two Abigail's Flowers from my backpack also evaporated. None of these items remained, or any of their materials (my eyeball! 
). The helms remained tho. Since I was alone and these are non-edible, non-burnable items, I can only think that meteors fall on and crushed them...
In addition to that, in an other world I wanted to mark wormholes with moonlens, one of which was in the mosaic again, in the meteor field. This moonlens also disappeared after some days, without leaving any moonrocks or the gem behind.
After this I went and made some experiments about it (did some science 
) and came to the conclusion that every item left on the ground gets destroyed by meteors. Each crafted item. The only exceptions are those which can be placed (like tooth traps), but even those get destroyed if left on the ground without "placing" them. If they are placed, they get "dropped" on the ground (and bees from the bee mine got out).
So, my question is: is this phenomen an intended feature, or a bug? Because it is quite annoying and I haven't heard of it before, so I guess it's not a very well known fact. And even if the items should get destroyed, shouldn't they drop their ingredients at least?
(PS: btw, good news: it seems that natural items get destroyed too... I could make whole stacks of stingers disappear with this method. It seems that we got an alternative to the eyeplant-trashcan!)