Fire's Clay Spawn is a mod I made to spawn clay underground like an ore. The clay can be set to spawn at the same rate and layers as Coal, Iron(default), Gold, Diamond, Redstone, Lapis, and Emerald. You can also manually override the maximum layer it generates at, the minimum layer it generates at, and the ore vein size. It also supports generation in styles similar to ores from Forestry and Brain Stone Mod. I plan to add support for generating in styles similar to ores from more mods as well. All of these settings can be applied to Hardened Clay generation as well. Also, the mod can be set to generate Stained Hardened Clay, adding a bit of color to your mines.
Retrogen can be achieved using SimpleRetrogen by cpw. Just add "the_fireplace.clayspawn.worldgen.WorldGeneratorClay" to the config.

For those of you saying this is a duplicate of Pam's Clay Spawn:
First of all, this mod is a lot more configurable than Pam's Clay Spawn. On mine, you can manually set the highest layer, lowest layer, vein size, and vein count, or input the name of a vanilla ore and some other modded ores to get the vein size and/or highest layer and/or lowest layer and/or vein count from. And you can generate Stained Terracotta and Glazed Terracotta.

Contact:

Feel free to contact me with feature requests, questions about the mod, bug reports, or pretty much anything else mod-related.

If you have a bug or crash to report, please use the issue tracker. If it is anything else, here are other ways to contact me.

Twitter (This one will get a quick response, notifications usually go instantly to my phone)

Discord (This one will get a faster response than Twitter, if my computer is on)

CurseForge

Minecraft Forum

Curse

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