ModsJava
Arbitrary Alloy
Make any alloy you can imagine. Free Minecraft Java mod for 1.12.2.
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Introduction
Arbitrary Alloy is a realistic metallurgy mod for Minecraft 1.12.2 Forge. It removes vanilla iron/gold tools, ingots, nuggets, and blocks, replacing them with a composition-based alloy system: mine real-world metal ores, control carbon content through smelting, blend different compositions on a crafting table, and craft tools whose stats are dynamically determined by their metal composition — all while watching them slowly corrode over time.
Core Gameplay
Mine → Smelt (carbon ingot) → Re-smelt (decarburize) → Blend (average) → Craft tool → Corrode
| Stage | Description |
|---|---|
| Mining | 12 real-world metal ores (Cu, Sn, Zn, Pb, Ni, Ag, Al, Mn, Cr, Ti, W, Pt) + vanilla iron/gold ores |
| Smelting | Smelt any metal ore → metal ingot with ~93-97% metal + 3-7% random carbon |
| Decarb | Put a carbon-containing ingot back in the furnace → reduced carbon by 20%-50% (hacks furnace input slot NBT.Therefore, unknown alloy ingots may appear when only one metal ingot is fired.) |
| Blending | 2-4 ingots of any composition in shapeless crafting → same count, averaged composition |
| Tools | 2-3 same-composition ingots + sticks → Sword/Pickaxe/Axe/Shovel/Hoe with dynamic stats |
| Corrosion | Tools lose durability over time; accelerated in water (×2), rain (×1.5), humid biomes (×1.3) |
Removed Vanilla Content
All iron/gold tools, ingots, nuggets, blocks, armor, horse armor, iron doors, and their crafting/furnace recipes.
Configuration
Config file: .minecraft/config/arbitraryalloy.cfg
| Category | Key | Default | Description |
|---|---|---|---|
| Carbon | carbonInitialMin |
0.03 | Minimum carbon from ore smelting |
| Carbon | carbonInitialMax |
0.07 | Maximum carbon from ore smelting |
| Carbon | carbonReductionMin |
0.20 | Minimum carbon reduction per re-smelt |
| Carbon | carbonReductionMax |
0.50 | Maximum carbon reduction per re-smelt |
| Corrosion | corrosionInterval |
1200 | Ticks between corrosion checks (60s) |
| Corrosion | corrosionChance |
0.05 | Base chance of durability loss per check |
| OreGen | oreCountCopper ~ oreCountPlatinum |
varies | Veins per chunk for each ore |
| OreGen | oreVeinSize |
8 | Maximum vein size |
| Tools | baseDurabilityIron |
250 | Base durability |
| Tools | baseSpeedIron |
6.0 | Base mining speed |
| Tools | baseDamageIron |
2.0 | Base attack damage |
| Tools | baseEnchantabilityIron |
14 | Base enchantability |
Verified by MCModsHub
- Ships as arbitraryalloy-1.0.0.jar — drop this file into the mods folder
- Download size: 84 KB
- Download link checked 24 Aug 2026 — working
These come from our own check of the pack file, not from the source page.