The ocean is a fantastic source of inspiration. These Sand Dollar Bath Bombs were inspired by the textures of the seashore and the treasures found there. The Sand Dollar Mold creates the perfect bath bomb size and shape, while Tropical Vacation Fragrance Oil gives the bath fizzies a light beachy scent.
This recipe consists of the bath bomb basics: baking soda (sodium bicarbonate) and citric acid. A touch of Epsom salt gives the bath water additional skin-loving properties, but could be omitted if you prefer. Polysorbate 80 prevents the coconut oil and micas in this recipe from pooling on top of the water and clinging to the side of the tub.
What You’ll Need:
Two Sand Dollar Molds
14 oz. Sodium Bicarbonate (Baking Soda) (About 1 1/2 cups)
7 oz. Citric Acid (About 3/4 cup)
3 oz. Epsom Salt, Extra Fine
2 oz. Coconut Oil
6 mL Polysorbate 80
9 mL Tropical Vacation Fragrance Oil
King’s Gold Mica
Super Pearly White Mica
Witch Hazel in Spray Bottle
Droppers
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ONE: In a large bowl, mix together the baking soda, citric acid, and Epsom salt. To get rid of clumps in the mixture, you can push the powders through a sifter or break them up with your fingers. Citric acid has a tendency to take off nail polish, so wear gloves to protect your manicure. Thoroughly stir the ingredients together.
NOTE: Usually our bath bomb recipes are measured by volume rather than weight. We used weight for this recipe to help estimate how much bath bomb mixture would be needed to fill up the cavities. Feel free to use whatever measurement you are more comfortable with. For reference, we found 1 cup of baking soda is approximately 10 ounces, while 1 cup of citric acid is approximately 8 ounces.
TWO: Add 1 teaspoon of King’s Gold Mica and use your hands or a whisk to fully mix it into the powders.
THREE: Melt the coconut oil in the microwave using 30-60 second bursts. Pour 2 ounces of the melted oil, 9 mL of Tropical Vacation Fragrance Oil, and 6 mL of polysorbate 80 into a small fragrance oil-safe container. Use a spoon to fully mix the ingredients together.
FOUR: Pour the oil mixture into the powder mixture and use your hands to fully incorporate the two.
FIVE: Test the consistency of the bath bomb mixture. The perfect consistency for molding is a texture similar to damp sand that holds its shape when squeezed. If it’s too dry, use one hand to spritz the mixture with witch hazel and one to mix. Continue spritzing until the mixture holds its shape when squeezed. Below, you can see that the mixture forms a ball when squeezed. This means that the mixture will hold its shape in the mold as well.
SIX: Fill the sand dollar mold cavities with bath bomb mixture. Press the mixture firmly into the mold and smooth the backs with your fingers. Allow them to dry for at least 4 hours or up to overnight. To remove, gently press the back of the mold until the bath bombs pop out.
SEVEN: Once the bath bombs have been removed, use a dry paintbrush to dust the tops with Super Pearly White Mica. Doing so helps the star shape in the center pop. If you’d like more contrast, mix 1/2 teaspoon Super Pearly White Mica with 1/2 Tbsp. 99% isopropyl alcohol and paint the mixture onto the bath bombs. Allow to dry for several minutes and enjoy!
- Two Sand Dollar Molds
- 14 oz. Sodium Bicarbonate (Baking Soda) (About 1½ cups)
- 7 oz. Citric Acid (About ¾ cup)
- 3 oz. Epsom Salt, Extra Fine
- 2 oz. Coconut Oil
- 6 mL Polysorbate 80
- 9 mL Tropical Vacation Fragrance Oil
- King's Gold Mica
- Super Pearly White Mica
- Witch Hazel in Spray Bottle
- Droppers
- In a large bowl, mix together the baking soda, citric acid, and Epsom salt. To get rid of clumps in the mixture, you can push the powders through a sifter or break them up with your fingers. Citric acid has a tendency to take off nail polish, so wear gloves to protect your manicure. Thoroughly stir the ingredients together. NOTE: Usually our bath bomb recipes are measured by volume rather than weight. We used weight for this recipe to help estimate how much bath bomb mixture would be needed to fill up the cavities. Feel free to use whatever measurement you are more comfortable with. For reference, we found 1 cup of baking soda is approximately 10 ounces, while 1 cup of citric acid is approximately 8 ounces.
- Add 1 teaspoon of King's Gold Mica and use your hands or a whisk to fully mix it into the powders.
- Melt the coconut oil in the microwave using 30-60 second bursts. Pour 2 ounces of the melted oil, 9 mL of Tropical Vacation Fragrance Oil, and 6 mL of polysorbate 80 into a small fragrance oil-safe container. Use a spoon to fully mix the ingredients together.
- Pour the oil mixture into the powder mixture and use your hands to fully incorporate the two.
- Test the consistency of the bath bomb mixture. The perfect consistency for molding is a texture similar to damp sand that holds its shape when squeezed. If it's too dry, use one hand to spritz the mixture with witch hazel and one to mix. Continue spritzing until the mixture holds its shape when squeezed. Below, you can see that the mixture forms a ball when squeezed. This means that the mixture will hold its shape in the mold as well.
- Fill the sand dollar mold cavities with bath bomb mixture. Press the mixture firmly into the mold and smooth the backs with your fingers. Allow them to dry for at least 4 hours or up to overnight. To remove, gently press the back of the mold until the bath bombs pop out.
- Once the bath bombs have been removed, use a dry paintbrush to dust the tops with Super Pearly White Mica. Doing so helps the star shape in the center pop. If you'd like more contrast, mix ½ teaspoon Super Pearly White Mica with ½ Tbsp. 99% isopropyl alcohol and paint the mixture onto the bath bombs. Allow to dry for several minutes and enjoy!
How many miles will i need for the instructions provided?
*molds not miles
We recommend two molds. The recipe makes 7-8 bath bombs, but the mold only has 4 cavities. You can also make 2 smaller batches, that way you only need 1 mold.
some of the mixture stuck to the star part of the mold. I crumbled them in a bowl and re molded. The mixture still had the consistency of slightly wet sand. Should I add more dry ingredients? I also added a little Cyclomethicone to the mold so the bomb wouldn’t stick.
The bath bombs may be a bit wet, or they may need more time in the mold. How long did they dry? Also, is it pretty humid where you are?
How can I make my bath bomb float on the top? it directly sink to the bottom 😔
I’m not entirely sure how to make them float. Some of our recipes float, and some sink to the bottom. Can you tell me a bit more about what’s in your recipe?
-Kelsey with Bramble Berry
II made the Sand Dollar Bath Bombs with the exact ingredients
This recipe sank for us as well. It may be the oil, salt, etc. I’m not quite sure how to make them float. They do still fizz really nicely though.
-Kelsey with Bramble Berry
Corn starch makes them float……
I would like to make these as party favors. Should I shrink wrap them or just put in a clear cellophane bag? Do you sell shrink wrap that is round? Do you sell labels for this product? This is my first attempt at making bath bombs!
You can shrink wrap or wrap them in cellophane, either way works well. Our Large Shrink Wrap Soap Bands may fit these bath bombs. To be sure, you can request a sample from our customer service team by emailing info(at)brambleberry(dot)com or calling 877-627-7883 between 9 a.m. and 4 p.m PST.
Large Shrink Wrap Bands: https://www.brambleberry.com/Shrink-Wrap-Soap-Bands-Large-P6540.aspx
We don’t have labels for this project, but you can create your own using online templates. Someone on teachsoap.com/forum may have suggestions for what services they use to create labels.
-Kelsey with Bramble Berry
Could you use fine dead sea salt in place of Epson salt?
Yep, that will work just fine. You can use the same amount as the Epsom salt in this recipe (3 ounces).
-Kelsey with Bramble Berry
Fine grained Dead Sea salt: https://www.brambleberry.com/Fine-Grained-Dead-Sea-Salt-P4085.aspx
Thank-you Kelsey.
Very pretty and summery! I can’t wait to try this! Can you use poly 20 vs 80, since that’s what I have on hand?
Polysorbate 20 works best for emulsifying lighter and smaller amounts of oils, like fragrance or essential oils. Polysorbate 80 works better because it can emulsify the heavier coconut oil. You can try the 20 in a small test batch to see if it emulsifies well, if not 80 works well.
-Kelsey with Bramble Berry
your PRINTED directions are wrong you have 1 oz of baking soda when it should be 14 oz… I was about to make it but I KNOW that it usually is more baking soda then citric acid, check the printed directions they are wrong they say 1 oz when ti should read 14 oz, so who ever prints this MAKE A NOTE 14 oz of baking soda is needed for this recipe
Those directions are fixed, thanks Gina. 🙂
-Kelsey with Bramble Berry
The Sand Dollar bath bombs was my first attempt at making bath bombs. It was so easy and I love them. I left them overnight and then unmolded them. They were perfect this morning, but tonight I see that they are all developing cracks through the center. Can you help me troubleshoot this problem? THANKS
Absolutely. Do they feel pretty dry and powdery to the touch, or more soft and wet?
-Kelsey with Bramble Berry
They were hard and popped out of the mold without a problem, holding their shape without crumbling or falling apart. I used one in the bath and it didn’t seem powdery. It broke into chunks when I broke it apart. But they were absolutely not soft and wet. I spritzed the mixture with witch hazel using maybe 5 or 6 sprays, mixing well, then packing very tightly into the mold. I live in Colorado and it is very, very dry here with humidity usually around 10%, so that is why I sprayed with witch hazel.
I think they may need some more liquid. In dry climates, you may find you need quite a bit of witch hazel. Just keep spritzing with one hand and mixing with the other until the mixture feels like wet sand and holds its shape when squeezed. That will prevent cracking and dryness. You can see that texture here: https://www.youtube.com/watch?v=8bjpsQXt6NU&t=58s
-Kelsey with Bramble Berry