## Cold Process Soap Cold process soap combines oils with lye (sodium hydroxide) through saponification. ⚠️ **Safety**: Lye is caustic. Wear gloves, goggles, long sleeves. Work in a ventilated area. ### Basic Recipe (makes ~4 bars) - Olive oil: 10 oz (40%) - Coconut oil: 7.5 oz (30%) - Shea butter: 5 oz (20%) - Castor oil: 2.5 oz (10%) - Lye (NaOH): 3.5 oz (use a soap calculator to verify!) - Distilled water: 8 oz - Essential oils: 1 oz (optional) ### Step 1: Lye Solution Always add lye TO water (never the reverse — exothermic reaction). Stir until dissolved. It will heat up to 200°F. Set aside to cool. ### Step 2: Melt Oils Melt coconut oil and shea butter. Add olive and castor oil. Cool to about 110°F. ### Step 3: Combine When both are around 100-110°F, slowly pour lye solution into oils. Blend with a stick blender. ### Step 4: Trace Blend until the mixture reaches "trace" — a pudding-like consistency where drizzles leave a trail. ### Step 5: Additives At light trace, add essential oils, colorants, or botanicals. ### Step 6: Mold and Cure Pour into molds. Insulate for 24 hours. Unmold and cut. Cure for 4-6 weeks before use.