Talk:Amulet of life/@comment-72.209.129.38-20120219041532

I am currently level 52; in the past, this item has shown up in research previews, but I never chose it because I wanted to do other things; now that I have customers asking for it, I cannot find it to research it!

Can anyone tell me whether research items disappear from the menu once you (or your worker) reach a certain level? If so, why is this????