ActuallyAdditions/src/generated/resources/assets/actuallyadditions/blockstates/black_quartz_slab_block.json

{
  "variants": {
    "type=top": {
      "model": "actuallyadditions:block/black_quartz_slab_block_top"
    },
    "type=bottom": {
      "model": "actuallyadditions:block/black_quartz_slab_block"
    },
    "type=double": {
      "model": "actuallyadditions:block/black_quartz_block"
    }
  }
}