Measure out your butter and oil and place them in a heat-proof jug or beaker.
Melt your butter and solid oil. You will want to make use of a water bath to do this. Simply fill a saucepan with a few inches of water and bring to a boil. Once boiling, turn the heat down to a simmer and place the jug/beaker into the water. Allow to melt for around 10-15 minutes, or until the solids have completely melted.
Now that the butter has melted, we can add our mica.
Now add your fragrance oil, if you are using a fragrance oil, you can add it right away. If using an essential oil, it’s best to let it cool for a minute first to get the most out of it.
Pour the melted ingredients into silicone molds, being careful not to spill. Keep in mind that the mixture is still very warm at this point. Let them sit for around 15 minutes, just so they begin to cool. Then you can go ahead and pop them in the fridge. I’d leave for at least 1 hour, but you can leave them for as long as you like.
Important: Make sure you’re careful when you get in and out of the bath, as I’ve found that these can make the bath a little slippery. Just be cautious.It’s best to keep these stored in the fridge, especially if you live in a warm climate.To use, just drop one homemade bath melt into a hot bath and enjoy a soothing, relaxing soak that should leave your skin feeling lovely and soft!