{
    "type": "tfc:alloy",
    "result": "gtceu:invar",
    "contents": [
        {
            "metal": "tfc:nickel",
            "min": 0.25,
            "max": 0.35
        },
        {
            "metal": "tfc:cast_iron",
            "min": 0.65,
            "max": 0.75
        }
    ]
}