# Sovereignty Module: Fire the Earth

## Complete Ceramics, Glazing, and Kiln Mastery Guide

Ceramics provide waterproof containers, building materials, and industrial components. This campaign covers advanced clay work, glaze chemistry, and kiln construction for producing professional-grade pottery.

### Chapter 1: Clay Preparation

| Step | Action | Purpose | Details |
|---|---|---|---|
| 1 | Dig raw clay | Source material | Look for: blue/gray subsoil, creek banks, road cuts |
| 2 | Slake in water (24-48 hours) | Break down lumite | Fill bucket, cover clay with water, stir |
| 3 | Screen through mesh (30-60 mesh) | Remove stones, roots, debris | Pour slurry through window screen |
| 4 | Settle (24 hours) | Separate clay from sand | Clay stays suspended longer than sand |
| 5 | Decant water | Remove excess water | Pour off clear water on top |
| 6 | Dry to workable consistency | Ready for use | Spread on plaster bat or canvas |
| 7 | Wedge (knead) 100+ times | Remove air bubbles, homogenize | Ram's head or spiral method |

### Chapter 2: Forming Methods

| Method | Skill Level | Best For | Wall Thickness | Production Speed |
|---|---|---|---|---|
| Pinch pot | Beginner | Small bowls, cups | 1/4-3/8 inch | Slow |
| Coil building | Beginner-intermediate | Large vessels, sculptural | 1/4-1/2 inch | Moderate |
| Slab construction | Intermediate | Flat items, boxes, tiles | 1/4-3/8 inch | Moderate |
| Wheel throwing | Intermediate-advanced | Symmetrical vessels | 1/8-1/4 inch | Fast |
| Mold pressing | Intermediate | Repeated identical forms | 1/4-3/8 inch | Fast (after mold made) |

### Chapter 3: Kiln Types

| Kiln Type | Max Temperature | Fuel | Construction Difficulty | Capacity | Best For |
|---|---|---|---|---|---|
| Pit fire (open) | 1,200-1,500F | Wood | Very low | 10-50 pieces | Primitive pottery (unglazed) |
| Sawdust kiln | 1,200-1,600F | Sawdust | Low | 5-20 pieces | Decorative, burnished ware |
| Updraft kiln (catenary arch) | 2,300F+ | Wood | Moderate | 20-100 pieces | All ceramics, glazed ware |
| Downdraft kiln | 2,400F+ | Wood/gas | High | 50-200 pieces | Professional production |
| Anagama (tunnel kiln) | 2,400F+ | Wood (continuous) | High | 100-500 pieces | Ash-glazed stoneware |
| Electric kiln | 2,300F | Electricity | Low (purchase) | 10-50 pieces | Precise control, clean |

### Chapter 4: Glaze Chemistry

| Glaze Component | Function | Common Sources | Temperature Range |
|---|---|---|---|
| Silica (SiO2) | Glass former (main ingredient) | Quartz sand, flint | All temperatures |
| Alumina (Al2O3) | Stiffener (prevents running) | Clay, feldspar | All temperatures |
| Flux (melts silica) | Lowers melting point | See flux table below | Varies by flux |
| Colorant | Adds color | Metal oxides (see below) | All temperatures |
| Opacifier | Makes glaze opaque | Tin oxide, zirconium | All temperatures |

| Flux | Temperature Range | Source | Notes |
|---|---|---|---|
| Lead oxide | Low fire (1,600-1,900F) | Galena, lead compounds | TOXIC — avoid for food vessels |
| Borax | Low fire (1,600-1,900F) | Borax mineral | Safe, common |
| Soda (Na2O) | Mid-high fire | Soda ash, feldspar | Common in stoneware |
| Potash (K2O) | Mid-high fire | Wood ash, feldspar | Free from hardwood ash |
| Calcium (CaO) | High fire (2,200-2,400F) | Limestone, wood ash, bone | Durable, food-safe |

| Colorant | Color Produced | Amount (% of glaze) |
|---|---|---|
| Iron oxide (Fe2O3) | Tan, brown, red, black (depending on amount/atmosphere) | 1-10% |
| Copper oxide (CuO) | Green (oxidation), red (reduction) | 1-5% |
| Cobalt oxide (CoO) | Blue (intense, reliable) | 0.5-2% |
| Manganese dioxide | Purple, brown, black | 2-8% |
| Rutile (TiO2) | Tan, cream, variegated | 3-8% |

### Chapter 5: Firing Schedule

| Stage | Temperature Range | Rate | Duration | Purpose |
|---|---|---|---|---|
| Water smoking | Room temp → 400F | Slow (100F/hour) | 3-4 hours | Drives off physical water |
| Burnout | 400-1,000F | Moderate (150F/hour) | 4-5 hours | Burns organic matter |
| Quartz inversion | 1,063F (critical) | Slow through this point | Hold 30 min | Quartz crystal structure changes (cracking risk) |
| Sintering/vitrification | 1,000F → target temp | Moderate-fast (200F/hour) | 4-8 hours | Clay particles fuse |
| Soak at peak | Target temperature | Hold | 30-60 minutes | Even heat distribution, glaze maturity |
| Cooling | Target → room temp | Slow (natural cooling) | 12-24 hours | Prevent thermal shock cracking |

### Chapter 6: Wood Ash Glaze (Free Glaze Recipe)

| Step | Action | Details |
|---|---|---|
| 1 | Collect hardwood ash (oak, maple, hickory) | Burn clean wood, collect white/gray ash |
| 2 | Sieve ash through 60-mesh screen | Remove charcoal chunks |
| 3 | Wash ash (optional — reduces flux, mellows glaze) | Soak in water 24 hours, pour off water (×3) |
| 4 | Mix: 40% ash + 40% feldspar + 20% clay | Basic ash glaze recipe (cone 6-10) |
| 5 | Add water to cream consistency | Should coat finger and show fingerprint |
| 6 | Apply to bisque-fired pottery (dip or brush) | 1/16 inch thick coating |
| 7 | Fire to cone 6-10 (2,200-2,400F) | Reduction atmosphere = best colors |

Result: Beautiful, durable, food-safe glaze in earth tones (green, brown, amber) — completely free from natural materials.

### Reference Card

1. Clay test: roll coil, wrap around finger. Good clay bends without cracking. Add sand if too sticky.
2. Dry slowly: 1-2 weeks minimum. Even drying prevents cracking. Cover loosely, turn daily.
3. Bone dry before firing: any moisture = explosion in kiln. Wait until clay is room temperature to touch.
4. Bisque fire first (1,800F): makes pottery hard but porous (absorbs glaze). Then glaze fire (2,200F+).
5. Wood ash = free glaze: 40% ash + 40% feldspar + 20% clay. Fire to cone 6-10. Food-safe.
6. Quartz inversion (1,063F): go slow through this temperature both heating AND cooling. Cracking risk.
7. Kiln must be dry before first firing: slow fire (200F) for 24 hours to drive moisture from kiln walls.
8. Reduction atmosphere (limited oxygen): produces best colors. Achieved by closing damper partially.