This page describes the ore generation configs for Minecraft 1.13.2 and up. In previous versions, all ore settings are in the normal config config. Versions for 1.12.2 and earlier did not support custom ore spawns.

Fun Ores can be made to spawn any type of block during world generation. These ore config files are located in config/funores/ore_generation. You can add or remove files however you like, but the default files will be regenerated if the folder is empty. The JSON format is described in detail below.

Spawning blocks with tile (block) entities is not tested but should work. However, tile entities tend to cause lag, so this should be done sparingly, if at all. I do not recommend this unless you know what you are doing.

One notable feature is the ability to spawn multiple block types in a single vein (specified by the blocks array). Each block in the vein is selected separately from this list. Each block entry is also assigned a weight, similar to loot tables. Higher weights mean a block is more likely to be selected. You can also include an entry without the block property (just weight), which will not replace blocks if selected. This could be used to create "sparse" ore veins.

• blocks - Array of blocks to spawn in the vein, along with the weight of each block. Must have at least one element.
  • block - The block ID. If omitted, the block is considered "empty" and no changes will be made to the world if selected.
  • weight - The weight of the block (defaults to 1 if missing)
• replaces - The block(s) the ore will replace, specified by a block tag (eg forge:stone)
• frequency - May contain one or both of rarity and count. Both default to 1 if omitted.
  • rarity - The chance (1 in N) that any given chunk will spawn this ore. Higher values will make the ore vein more rare.
  • count - The number of veins spawned if the rarity check passes.
• size - The "size" of the vein. This does not necessarily equal the number of blocks per vein, but tends to be close.

• min_height - The lowest Y-level to spawn at.
• max_height - The highest Y-level to spawn at.
• dimensions - The dimensions the ore may spawn in. Each element is a dimension ID (string) like "minecraft:overworld".
• biomes - Not implemented at time of writing, still considering how to do this.

This file will create deposits of cobblestone throughout the world. Some of the blocks in each "vein" will be mossy cobblestone, but most will be plain cobblestone. A few blocks may be left unchanged because of the last element in the blocks array. This makes the veins look slightly more random in shape.

{
    "blocks": [
        {
            "block": "minecraft:cobblestone",
            "weight": 16
        },
        {
            "block": "minecraft:mossy_cobblestone",
            "weight": 3
        },
        {
            "weight": 1
        }
    ],
    "replaces": "forge:stone",
    "frequency": {
        "rarity": 2,
        "count": 20
    },
    "size": 24,
    "min_height": 0,
    "max_height": 128,
    "dimensions": [
        "minecraft:overworld"
    ],
    "biomes": []
}