Everything You Need to Know About Our Tea Tree, Eucalyptus & Activated Charcoal Soap (Including the Recipe!)

Our Tea Tree, Eucalyptus & Activated Charcoal Soap is an absolute powerhouse of natural goodness! I originally created it for two very active members of my family, my father and my brother. They both work very long, physically demanding jobs, and when they’re not at work, you'll usually find them on a jiu-jitsu mat. With so much time spent in gyms and close contact training environments, they're very aware of the bacteria and grime that can build up through sweat and shared equipment.

They had often bought soaps made with tea tree and eucalyptus specifically for use after training, so it made sense for me to craft a bar just for them. Both tea tree and eucalyptus essential oils are known for their antibacterial and antimicrobial properties, while activated charcoal helps to draw out impurities, and kaolin clay brings a touch of gentleness to keep the soap balanced enough for everyday use.

This is the soap for people with an active lifestyle who need something a little more robust, a bar that really supports the skin after a long day of training, working, or moving.

Why These Ingredients Work So Well

Tea Tree Essential Oil

• Widely recognised for it's antibacterial & antimicrobial, helping keep the skin clean, making it a staple in products for active or blemish prone skin.
• Often used to calm redness and irritation, leaving the skin feeling more balanced.
• Supports skin hygiene, especially valued after time in gyms or training environments, where sweat and bacteria can build up.
• Refreshing feel, helps the skin feel thoroughly cleansed after activity.
  

Eucalyptus Essential Oil

• Like tea tree, eucalyptus also has antibacterial & antimicrobial properties helping reduce microbes on the skin's surface.
• Commonly included in balms and rubs to help soothe the skin after physical activity.
• Cooling & restorative providing a naturally refreshing sensation after exercise or long days.
  

Activated Charcoal

• Absorbs impurities, draws out dirt, sweat, and excess oils from the skin's surface.
  
• Balances oils by helping to control sebum without stripping the skin.
  
• Often used to unclog pores, leaving the skin feeling fresh and clear.
  
• Deeply cleansing, ideal for people who want a thorough cleanse after gyms or outdoor activity.
  

Kaolin Clay

• Gentle cleansing, softly cleanses without stripping natural oils.
  
• Calms and soothes sensitive or irritated skin.
  
• Absorbs excess oils, leaving skin feeling soft, smooth, and balanced.
  
• Offsets stronger ingredients like charcoal and essential oils, keeping the soap suitable for daily use.
  

 

The Base Oils

Shea Butter

• Rich in vitamins A and E, this deeply moisturises while supporting skin elasticity. It also helps create a conditioning, creamy lather.
  

Coconut Oil

• Adds firmness to the bar and provides excellent cleansing properties, leaving skin feeling fresh (but not stripped, thanks to the balance with other oils).
  

Olive Oil

• A gentle, skin loving oil that makes for a nourishing and mild bar.
  

Castor Oil

• Boosts lather, giving the soap a bubbly finish while also bringing in additional moisturising qualities.
  

Together, these oils create a well balanced bar, cleansing, gentle, bubbly, creamy, firm and long lasting.

The Recipe:

Beginner Safety Reminders

Before you dive in, here are a few non negotiables when working with lye and hot soap batter:

• Protect yourself: Always wear gloves, goggles, and long sleeves. Lye is caustic and can burn skin on contact.
  
• Ventilation matters: Mix your lye solution near an open window or in a well ventilated space. Never breathe in the fumes.
  
• Add lye to water, never water to lye: This prevents dangerous splashing or volcanic reactions.
  
• Use heat safe containers: Avoid aluminium or tin,  lye reacts with certain metals. Stick with stainless steel, heat resistant plastic, or tempered glass.
  
• Label your tools: Anything that touches lye or raw soap should be used only for soap making, never for food.
  
• Clean up carefully: Wash tools immediately after use, wearing gloves, and keep them out of reach of children or pets until they're safe.
  
• Patience is key: Soap needs time to cure, don’t be tempted to use it before the full 6 weeks.
  

Think of this checklist as your soap making "seatbelt". It might feel cautious, but it ensures your process is safe, smooth, and enjoyable.

Ingredients:

• 250g Shea Butter
  
• 250g Coconut Oil
  
• 400g Olive Oil (or Olive Pomace Oil)
  
• 100g Castor Oil
  
• 136.96g Lye
  
• 246.93g Distilled Water
  
• 6g Kaolin Clay
  
• 9g Activated Charcoal
  
• 15g Tea Tree Essential Oil
  
• 15g Eucalyptus Essential Oil
  

Equipment:

• Safety goggles, gloves, long sleeves
  
• Digital scale (accurate to 0.01g)
  
• 2L jugs ×3 (for lye solution and oils)
  
• 4 small dishes for additives (at least 25ml, I use 50ml)
  
• Stick blender, heat resistant spatula, spoons
  
• Soap mould (lined if not silicone)
  
• Parchment/freezer paper (if required)
  
• Thermometer (optional)
  
• Sharp knife or soap cutter
  

Method (Cold Process – Heat Transfer Method)

Step 1: Measure Your Base Oils

• Measure out your solid oils (shea butter and coconut oil) into one jug.
  
• Measure out your liquid oils (olive oil and castor oil) into a separate jug.

Step 2: Prepare the Lye Solution

• Weigh your distilled water into a heat-safe jug.
  
• Carefully weigh out your lye.
  
• Slowly pour the lye into the water (never water into lye), stirring gently until dissolved. Do this near a window or under good ventilation, as the fumes will be strongest at this stage.
  

Step 3: Melt the Solid Oils with the Heat Transfer Method

• Pour the hot lye solution directly into your jug containing the solid oils.
  
• Stir every couple of minutes until the heat of the lye solution has melted the oils completely.

Step 4: Prepare Your Additives

• While the oils are melting, measure out your essential oils, kaolin clay and activated charcoal into separate dishes. (If you’re confident in your ability to measure the essential oils accurately you can add them to the same container and skip the next step.
• Combine the essential oils and give it a mix, once well combined, put 15g of that mixture back into the now empty dish.
• Add the kaolin clay to one of those mixtures and the activated charcoal to the other and mix thoroughly. This step ensures there are no clumps.
  

Step 5: Combine Liquid Oils With Now Melted Oil/Lye Solution

• Add the liquid oils to the melted oils/lye solution.
  
• Stick blend to a light trace.
  

Step 6: Split The Batter

• Divide batter into two jugs.
  
• Stir the kaolin mixture into one, charcoal mixture into the other.
  
• Continue to stick blend until everything is well incorporated (go from light to dark if using the same utensils for both colours)
  

Step 6: Pour into the Mould

• Pour your soap batter into your lined soap mould. The easiest option is to pour one colour in and then the next, but this is where you can get creative so go wild!
  
• Tap the mould gently on the counter to release any air bubbles.
  

Step 7: Set and Cure

• Cover and insulate your mould if desired.
  
• Allow the soap to set for 24–48 hours.
  
• Once firm, unmould and slice into bars.
  
• Leave to cure in a cool, dry place for at least 6 weeks. This allows the soap to harden and ensures it's gentle on the skin.

Troubleshooting Tips

Even with a tried and true recipe, soap can sometimes misbehave. Don't worry,  it happens to all of us! Here are a few common issues you might encounter with this recipe and how to handle them:

1. Soap Overheating

Why it happens:

Essential oils can cause your soap to heat up more than usual during saponification.

What to do:

• Avoid insulating the mould too heavily, sometimes leaving it uncovered is best.
  
• If you notice cracking or a darker spot forming in the centre (signs of overheating), pop the mould in the fridge for a few hours.
  

2. Soap Reaching Trace Too Quickly

Why it happens:

Activated charcoal can speed things up, especially if your oils or lye solution are too warm.

What to do:

• Stick blend in short bursts and switch to hand stirring once the batter starts to thicken.
  
• If the batter thickens too quickly, don’t panic, just spoon it into the mould and smooth it down. It will still cure beautifully.
  

3. Separation or Oil Pools

Why it happens:

Additives weren't fully blended in, or the batter wasn't mixed to a stable trace before pouring.

What to do:

• Always premix additives with a little oil (as in the method above) to prevent clumps.
  
• Make sure you've reached at least a light trace before pouring into the mould.
  

4. Soda Ash (White Powdery Layer on Top)

Why it happens:

Exposure to air while the soap is still soft can cause soda ash to form.

What to do:

• Spray the surface of the soap with isopropyl alcohol after pouring (optional but effective).
  
• Cover the mould lightly with cling film, making sure it doesn't touch the soap surface.
  
• If it still forms, don't worry, it's harmless and purely cosmetic. A quick rinse or trim will remove it.
  

5. Soap Sticking to the Mould

Why it happens:

Soap hasn't set long enough or the mould wasn't lined properly.

What to do:

• Give it more time, check again after 48 hours if it's too soft to unmould.
  
• If you're not using a silicone mould, line your mould with parchment or freezer paper before pouring.

A Note for Beginners

Soap making takes practice. Every batch teaches you something new, and small imperfections don't mean failure, they're part of the process. Even if your soap doesn't look perfect, it's still going to clean, nourish, and be completely usable.

Final Thoughts

This soap is designed for active people, after the gym, outdoor activity, or a demanding workday, the combination of tea tree, eucalyptus, charcoal, and clay offers a balanced, supportive cleanse.

We know not everyone wants to handle lye or spend a weekend making soap. If this is you, why not try our Tea Tree, Eucalyptus & Activated Charcoal Soap and enjoy all the benefits without the work.

And if you want to make your bar last even longer, pair it with a Soap Saver Bag to add gentle exfoliation or a Soap Dish to allow it to drain between uses and extend its life.

Join the Conversation!

Do you lead an active lifestyle? Have you tried charcoal soaps before? Share your tips, experiences, or questions in the comments, your insights could help someone else find their perfect post workout bar.