Cotton Resources adds default ores and configurable, JSON-based world generation for mods to use.

• A set of common ores for mods to use, to avoid having to regenerate ores if you add a new tech mod
• Fully configurable, JSON-based ore generation with blacklisting, whitelisting by biome or dimension
• Layered ores, which means you can easily create nether or any other type of ores with the same ore texture!