minecraft-assets/assets/minecraft/blockstates/stone.json

{
    "variants": {
        "": [
            { "model": "block/stone" },
            { "model": "block/stone_mirrored" },
            { "model": "block/stone", "y": 180 },
            { "model": "block/stone_mirrored", "y": 180 }
        ]
    }
}