When we got our first look at the archeology game mechanic coming to Minecraft in the 1.17 update — dubbed Caves and Cliffs — it was easy to imagine that you could create dirt, sand, and gravel half slabs with the new brush tool. However, a developer has dashed those hopes by explaining that dirt slabs actually aren't going to be coming to Minecraft.
Minecraft is a game that is centered around one square meter blocks and what you can do with them. However, it has allowed players to change some of those blocks into slabs that are half the size for quite some time, opening up new design possibilities.
Essentially all "solid" blocks — with the exception of metals — can be turned into slabs. Loose blocks, like dirt and sand, can't be turned into slabs (at least not yet) despite what it looks like when you're excavating artifacts, according to one Minecraft developer.
Based purely on the footage of what an excavation would look like — as well as the developers saying that you need to be "careful" when brushing artifacts — you can be forgiven for thinking that you can stop brushing at any point and get a less-than-full block. It even appeared that loose blocks could be treated like cakes, with fractions of the block being taken away, rather than being stuck with either half or full blocks.
Unfortunately, the disappearance of fractions of the block is merely an animation, similar to breaking regular blocks. If you stop brushing, the block will go back to being whole. The Caves and Cliffs update isn't releasing until the summer of 2021, though, so there is plenty of time for things to change.
It could be that allowing for dirt and sand to be turned into slabs would be impractical from the design side of things. The vast majority of the surface is made up of these loose blocks, after all. However, if it is possible at some point, having half slabs of dirt, gravel, and sand would be a game-changer for most players.
Source: Twitter