Soap Additives Guide
Clays, Honey, Oatmeal, Botanicals & More
What Are Soap Additives?
Additives are extra ingredients added to your soap recipe beyond the basic oils, lye, and water. They can provide color, exfoliation, lather boosting, hardness, and special properties. While completely optional, additives let you create unique, customized soaps.
Common Purposes:
- Colorants: Clays, charcoal, cocoa, botanicals
- Exfoliants: Oatmeal, poppy seeds, coffee grounds
- Lather Boosters: Honey, sugar, sodium lactate
- Hardeners: Salt, beeswax, sodium lactate
- Skin Benefits: Aloe, silk, milk powders
Clays
Clays add natural color and can provide gentle exfoliation. They also help anchor scents and add slip to shaving soaps.
| Clay Type | Color | Usage Rate | Properties |
|---|---|---|---|
| Kaolin (White) | White/cream | 1 tsp/lb oils | Mildest; sensitive skin; slip for shaving |
| Bentonite | Gray-green | 1 tsp/lb oils | Drawing; oily skin; excellent for shaving |
| French Green | Sage green | 1 tsp/lb oils | Mineral-rich; all skin types |
| Rose/Pink | Soft pink | 1 tsp/lb oils | Gentle; sensitive and mature skin |
| Rhassoul | Brown | 1 tsp/lb oils | Moroccan; conditioning; reduces dryness |
How to Add: Mix clay with a small amount of oil or water to create a slurry before adding at trace to prevent clumping.
Lather Boosters & Hardeners
| Additive | Usage Rate | Purpose | When to Add |
|---|---|---|---|
| Honey | 1 tbsp/lb oils | Lather boost, humectant, color | At trace; watch heat! |
| Sodium Lactate | 1 tsp/lb oils | Hardness, faster unmold | Add to cooled lye water |
| Salt | 0.5 tsp/lb oils | Hardness (small amounts) | Dissolve in water phase |
| Beeswax | 2% of oils | Hardness, longevity | Melt with oils; adds to SAP |
| Sugar | 1 tsp/lb oils | Lather boost | Dissolve in water phase |
Sugar Warning
Honey and sugar increase saponification heat. Don't insulate sugar/honey soaps. Put in refrigerator or freezer if soap starts to volcano.
Exfoliants & Botanicals
| Additive | Usage Rate | Exfoliation | Notes |
|---|---|---|---|
| Colloidal Oatmeal | 1 tbsp/lb oils | Gentle | Soothing, sensitive skin |
| Poppy Seeds | 1 tsp/lb oils | Medium | Classic look, effective scrub |
| Coffee Grounds | 1 tbsp/lb oils | Medium-Strong | Use dried grounds; adds brown |
| Corn Meal | 1 tsp/lb oils | Medium | Gardener's/mechanic's soap |
| Lavender Buds | 1 tsp/lb oils | Gentle | Decorative; turns brown in soap |
| Calendula Petals | 1 tsp/lb oils | Gentle | Stays yellow! Keeps color |
| Orange Peel Powder | 1 tsp/lb oils | Medium | Adds orange-brown color |
Botanicals in Soap: Most flowers and herbs turn brown in soap. For decorative botanicals, add them on top rather than mixing in.
Special Purpose Additives
| Additive | Usage Rate | Purpose |
|---|---|---|
| Activated Charcoal | 1 tsp/lb oils | Black color; drawing properties; facial bars |
| Cocoa Powder | 1 tbsp/lb oils | Brown color; subtle chocolate scent |
| Silk Fibers | 0.5 tsp/lb oils | Silkiness, slip; dissolve in lye water |
| Aloe Powder | 0.5 tsp/lb oils | Soothing; sensitive skin formulas |
| Milk Powders | 1 tbsp/lb oils | Creaminess, lather; easier than liquid milk |
Troubleshooting
| If… | Then… | Solution |
|---|---|---|
| Clumps of clay | Clay wasn't dispersed before adding | Mix clay with oil or water to make slurry first; add at thin trace |
| Soap overheated | Sugars in honey/sugar accelerated heat | Place in fridge/freezer immediately; reduce usage next time |
| Exfoliants sank | Soap was too thin when added | Wait until medium trace to add heavy exfoliants like seeds |
Ready to add some personality?
Use the SoapMath Soap Calculator to easily add any of these additives to your formula with automatic weight conversions.