This galaxy melt and pour soap swirls black charcoal soap and bright blue soap together with sparkly bio glitter, so each bar looks like a little piece of the night sky. It’s made in an oval mold with just two colors, so it’s quick and beginner-friendly. The secret is pouring both colors at the same time, nice and cool.
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Materials & Tools
- Clear melt and pour soap base, about 3 oz (1/4 cup) per oval cavity, divided into two cups
- Activated charcoal for the black
- A light blue colorant (I used Blue Slushie from Bramble Berry; a Stardust mica works too)
- Bio glitter (I used Moonlit Silver, made from plants instead of plastic)
- Oval 6 cavity soap mold
- Funnel pour cups
- Spray bottle of isopropyl alcohol
- Thermometer
- Optional: fragrance oil (I like Barnhouse fragrance oils)
Fragrance Amount
I left this test batch unscented so I could see how the design came out. If you add fragrance, I use 5 ml of fragrance oil per 16 oz of soap base. You can always use less, but I wouldn’t go over 5 ml per 16 oz.
How to Make Galaxy Melt and Pour Soap: Step by Step
1. Measure and Melt
Measure about 3 oz (1/4 cup) of clear base for each cavity you want to fill. I write the amount on the back of my mold so I don’t have to measure it every time. Divide the base into two funnel cups and melt. Mine were about 150°F and already starting to form a skin.
2. Color One Cup Blue
Mix the blue colorant with a little alcohol and stir it into the first cup. Choose a light, bright blue. A dark color won’t stand out against the black.
3. Color the Other Cup Black
Mix activated charcoal with a little alcohol and stir it into the second cup until it’s a deep black. Add a bit more if you need to.
4. Add Glitter and Let It Cool
Stir bio glitter into both cups, then let them cool. You want the soap as cool as you can get it so the two colors swirl instead of blending together. Stir again right before pouring so the glitter doesn’t sink. I aimed for about 115°F, but the soap got too clumpy once it dropped below about 122°F. I warmed both cups in the microwave for 10 seconds, and poured at about 126–127°F. The glitter held up fine after the quick reheat.
5. Pour Both Colors Together
Hold one cup in each hand and pour both colors into each cavity at the same time, swirling them as you go. Funnel cups make this much easier, because the soap glides out in a thin stream and the colors swirl together.
6. Spray and Let Set
Spray the tops with alcohol to pop the bubbles, then let the soaps set completely.
7. Unmold
Pop the soaps out of the mold. Each one has its own swirl of blue and black with glitter sparkling through it, like a galaxy.
Tips & What I Learned
- Pick a light contrast color. Bright blue pops against charcoal black. A dark glycerin color can get lost.
- Pour as cool as you can. Cooler soap keeps the colors from muddying together.
- Reheat in short bursts. If the soap gets clumpy, 10 seconds in the microwave is enough.
- Stir glitter right before pouring. It sinks in warm soap.
- Funnel cups help. They give you a thin, controlled stream for swirling.
Troubleshooting
My colors blended into gray.
The soap was too hot. Let it cool more before pouring, or pour faster so the colors don’t have time to mix.
The soap got too thick to pour.
Warm it for about 10 seconds and stir. I poured at about 126–127°F.
The glitter sank to the bottom.
Stir it in again right before pouring, and pour when the soap is cooler and thicker.
FAQ
How much soap does each oval cavity need?
About 3 oz, or 1/4 cup, in my oval mold.
Is bio glitter safe in soap?
The bio glitter I used is made from plants, not plastic. Whatever glitter you use, check that it’s labeled cosmetic-grade or skin-safe.
Can I use other colors?
Yes. Try a light green or purple with the charcoal. Just keep the second color light so it contrasts with the black.
How much fragrance should I use?
I use 5 ml per 16 oz of soap base. You can always use less, but I wouldn’t use more than 5 ml per 16 oz.
More Soap Ideas
- Black Neon Melt and Pour Soap
- Coral Lagoon Melt and Pour Soap
- How to Swirl Melt and Pour Soap
- All my melt and pour soap tutorials on YouTube
If you make this, I’d love to see it! Tag me on Instagram or Pinterest, and subscribe on YouTube for new soap tutorials.
