6Prismarine Slab is a shaped crafting recipe that uses 3 items: 3 Prismarine. Place the ingredients exactly in the pattern shown above. The pattern can sit anywhere on the grid as long as its shape stays the same. It needs the full 3×3 grid, so you have to use a crafting table.
You need 3 Prismarine — 3 items in total, arranged as shown in the crafting grid. The recipe gives you 6× Prismarine Slab.
Yes. The recipe needs the full 3×3 grid, which only a crafting table offers.
It is a shaped recipe: the arrangement matters. You can shift the pattern around the grid, but the shape must stay the same.
