While grass blocks are grouped with dirt blocks in the Creative inventory, the same is not true for nylium with netherrack.
- Open Building Blocks
- Locate grass blocks
- Locate dirt
- Locate nylium
- Locate netherrack
Dirt and grass blocks would be close together, and netherrack and nylium would also be.
Dirt and grass blocks are next to each other, but netherrack is very far from nylium; nylium appears near the top whereas netherrack is around halfway down.
Likely worth noting is that mycelium is far from dirt as well, however this predates 1.16 considerably.