User blog comment:FairyRaven/Fairy Tail Chapter 421: Wendy and Chelia, Review and Commentary/@comment-24039250-20150224014538/@comment-7418318-20150224143631

I seriously doubt they would just keep the crystal out in the open without covering it up. A big piece of cloth or a sufficiently big wooden box and no one could tell if there's a crystal with a frozen body or just a big piece of furniture inside.