Minecraft wiki entry for Hopper, associated text: A hopper collects items dropped on top of it if the space above the hopper not occupied by a storage block. In Java Edition, items are gathered from the entire 1 block space above the hopper, meaning that items sitting on partial blocks such as soul sand directly above a hopper can be collected. In Bedrock Edition, items are gathered from the lower 3⁄4 of the block space above the hopper, so items sitting on a lower slab or bed can be collected while items sitting on an enchanting table or horizontal grindstone cannot.[1] (Moreover, soul sand is a full block in Bedrock Edition.[2]) It is also possible for a hopper to collect items from inside a full, solid block, a situation that might come from items rising up through solid blocks or being summoned. Item entities are not collected when they are outside of the collection area however; for example, items on top of a stone block directly above a hopper are not collected. Collected items are placed in the leftmost empty slot of a hopper's inventory.