Minecraft wiki entry for Shulker_Box, associated text: Shulker boxes are portable chests: they keep their items when broken, which can be retrieved when placed again. This is different from other containers, which drop their contained items as item entities when broken. A shulker box drops itself as an item if pushed by pistons or destroyed by an explosion. Unlike most blocks with inventory, shulker boxes always drop themselves when destroyed by explosions. When a shulker box with items inside is held or in a container's inventory, the items are listed as properties.