Sovereignty Module: Extract the Metal
Complete Smelting and Ore Processing: From Rock to Refined Metal
Smelting transforms raw ore into usable metal, the foundation of tools, weapons, and machinery. This campaign covers ore identification, furnace construction, smelting techniques, and refining.
Chapter 1: Ore Identification
| Metal | Ore Name | Appearance | Test | Abundance | Smelting Temp |
|---|---|---|---|---|---|
| Iron | Hematite | Red-brown, heavy | Red streak on porcelain | Very common | 2,200-2,800°F |
| Iron | Magnetite | Black, magnetic | Attracts magnet | Common | 2,200-2,800°F |
| Iron | Bog iron | Brown, porous lumps | Found in bogs/swamps | Common (wetlands) | 2,000-2,400°F |
| Copper | Malachite | Green, banded | Green streak | Moderate | 1,980°F (pure Cu) |
| Copper | Azurite | Deep blue | Blue streak | Moderate | 1,980°F |
| Copper | Native copper | Reddish metal chunks | Already metallic | Rare | Melt only (no smelting) |
| Tin | Cassiterite | Black/brown, heavy | Heavy for size | Uncommon | 450°F (pure Sn) |
| Lead | Galena | Silver-grey, cubic crystals | Heavy, soft | Common | 620°F (pure Pb) |
| Silver | Native silver | White metal, tarnishes | Already metallic | Rare | 1,760°F (melt) |
| Gold | Native gold | Yellow metal, heavy | Already metallic, heavy | Very rare | 1,945°F (melt) |
| Zinc | Sphalerite | Yellow-brown, resinous | Difficult to identify | Common | Distillation required |
Ore prospecting: 1) Look in stream beds (heavy minerals concentrate in bends and behind rocks). 2) Check road cuts and cliff faces (exposed rock layers). 3) Look for color changes in rock (green = copper, red-brown = iron, white quartz veins = gold/silver). 4) Bog iron: look in swampy areas for orange-brown deposits in water or rusty-looking soil. 5) Test with magnet (magnetite sticks). 6) Streak test: scratch on unglazed porcelain (color of powder identifies mineral). 7) Weight test: metal ores are heavier than surrounding rock.
Chapter 2: Furnace Types
| Furnace | Max Temp | Metal | Fuel | Build Time | Difficulty | Output |
|---|---|---|---|---|---|---|
| Campfire (pit) | 1,500°F | Copper (native), lead | Wood/charcoal | 1 hour | Very low | Very small |
| Bowl furnace | 2,000°F | Copper, bronze, lead | Charcoal + bellows | 2-4 hours | Low | Small |
| Bloomery | 2,200-2,800°F | Iron (bloom) | Charcoal + bellows | 1-2 days | Moderate | Small-medium |
| Shaft furnace | 2,500-3,000°F | Iron (bloom/cast) | Charcoal + bellows | 2-5 days | Moderate-high | Medium |
| Blast furnace | 3,000°F+ | Cast iron | Charcoal/coke + forced air | Weeks-months | Very high | Large |
| Cupola | 2,800°F+ | Remelting cast iron | Coke + forced air | Days | High | Medium-large |
| Crucible | 2,500°F+ | Steel, bronze, brass | Charcoal in furnace | Hours | Moderate | Small |
Bloomery furnace construction: 1) Build cylindrical shaft: clay/mud bricks, 3-4 ft tall, 12-18 inch interior diameter. 2) Walls: 4-6 inches thick (insulation). 3) Tuyere hole: 4-6 inches from bottom (where bellows pipe enters). 4) Tap hole: at bottom (to drain slag). 5) Charge hole: at top (add ore and charcoal). 6) Bellows: double-chamber bellows providing continuous air blast. 7) Dry furnace thoroughly before first use (moisture = steam = explosion). 8) Line interior with refractory clay if available.
Chapter 3: Iron Smelting
| Stage | Temperature | Duration | What Happens | Fuel:Ore Ratio |
|---|---|---|---|---|
| Preheat furnace | 1,500°F+ | 1-2 hours | Dry and heat furnace walls | Charcoal only |
| Charge | N/A | 15 min | Add alternating layers of charcoal and ore | 1:1 by weight |
| Reduction | 2,200-2,400°F | 4-8 hours | Carbon monoxide reduces iron oxide to iron | Continuous charging |
| Bloom formation | 2,200-2,400°F | During smelt | Iron particles weld together in furnace | N/A |
| Slag tapping | N/A | Periodic | Liquid slag drains from tap hole | N/A |
| Bloom extraction | N/A | End of smelt | Remove bloom from furnace (break open if needed) | N/A |
| Bloom consolidation | 1,800-2,200°F | 30-60 min | Hammer hot bloom to expel slag | Forge fuel |
Iron smelting procedure: 1) Crush ore to walnut-sized pieces. 2) Roast ore in open fire (drives off moisture and sulfur, makes ore porous). 3) Preheat bloomery with charcoal fire (1-2 hours). 4) Begin charging: layer of charcoal, layer of roasted ore, repeat. 5) Maintain constant air blast with bellows (critical for temperature). 6) Continue charging as material sinks (4-8 hours total). 7) Tap slag periodically (liquid glass flows from bottom). 8) When smelt is complete: extract bloom (spongy mass of iron + slag). 9) Immediately hammer bloom while hot (consolidation: squeezes out slag, welds iron particles). 10) Result: wrought iron bloom ready for forging.
Chapter 4: Copper and Bronze
| Alloy | Composition | Melting Point | Properties | Use |
|---|---|---|---|---|
| Pure copper | 100% Cu | 1,984°F | Soft, malleable, conducts | Wire, vessels, roofing |
| Bronze (tin) | 88-92% Cu + 8-12% Sn | 1,750°F | Hard, casts well | Tools, weapons, bells |
| Brass | 60-70% Cu + 30-40% Zn | 1,700°F | Yellow, machinable | Hardware, instruments |
| Bell metal | 78-80% Cu + 20-22% Sn | 1,700°F | Resonant, hard | Bells, cymbals |
| Gunmetal | 88% Cu + 10% Sn + 2% Zn | 1,750°F | Strong, corrosion-resistant | Cannons, fittings |
Copper smelting: 1) Crush malachite/azurite ore. 2) Mix with charcoal (1:1 by weight). 3) Place in crucible or bowl furnace. 4) Heat with bellows blast to 2,000°F+. 5) Carbon reduces copper oxide to metallic copper. 6) Copper melts and pools at bottom. 7) Slag floats on top. 8) Pour off slag or let cool and break apart. 9) Copper ingot at bottom. 10) For bronze: re-melt copper, add 10% tin, stir, pour into mold.
Chapter 5: Refining and Alloying
| Process | Purpose | Method | Temperature | Difficulty |
|---|---|---|---|---|
| Remelting | Purify, reshape | Melt in crucible, skim slag | Metal's melting point | Low |
| Cupellation | Separate silver from lead | Melt lead-silver, blow air (lead oxidizes) | 1,750°F | Moderate |
| Cementation (steel) | Add carbon to iron | Pack iron in charcoal, heat for hours | 1,700°F | Moderate |
| Case hardening | Harden surface of iron | Heat in carbon-rich material | 1,500°F | Low-moderate |
| Quenching | Harden steel | Heat to critical temp, plunge in water/oil | 1,400-1,500°F | Low |
| Tempering | Reduce brittleness | Reheat quenched steel to lower temp | 350-700°F | Low |
| Annealing | Soften for working | Heat and cool slowly | Varies | Low |
Reference Card
- Charcoal, not wood (wood cannot reach smelting temperatures; charcoal burns 800°F hotter). 2. Air blast is critical (bellows provide oxygen that raises temperature; without forced air, no smelting). 3. Bog iron is the easiest start (found in swamps, lower smelting temperature, no mining needed). 4. Crush ore small (smaller pieces = more surface area = faster, more complete reduction). 5. Roast before smelting (pre-heating ore drives off moisture and sulfur, makes ore porous and reactive). 6. Hammer the bloom immediately (hot bloom must be consolidated by hammering; cold bloom is useless). 7. Slag is not waste (slag protects the bloom from oxidation during smelting; it's part of the process). 8. 10% tin makes bronze (copper alone is soft; adding 10% tin creates bronze, hard enough for tools and weapons).