// blockstate
{
  "variants" : {
    "formed=true,frame=true" : {
      "textures" : {
        "all" : "exkva:blocks/fission_corner"
      },
      "model": "exkva:block/reactor_casing"
    },
    "formed=false,frame=true" : {
      "model": "exkva:block/reactor_casing"
    },
    "formed=false,frame=false" : {
      "model": "exkva:block/reactor_casing"
    },
    "formed=true,frame=false" : {
      "model": "exkva:block/reactor_casing"
    }
  }
}

// model
{
    "parent": "block/cube_all",
    "textures": {
        "all": "exkva:blocks/fission_reactor_casing"
    }
}