Amethyst COFH World example

"Amethyst": {
        "template": "uniform",
        "block": "BiomesOPlenty:gemOre",
        "material": "minecraft:end_stone",
        "clusterSize": 4,
        "numClusters": 24,
        "minHeight": 5,
        "maxHeight": 256,
        "retrogen": "true",
        "biomeRestriction": "none",
        "biomes": [
            "all"
        ],
        "dimensionRestriction": "whitelist",
        "dimensions": [
            1
        ]
    }