Put the sea salt into a food processor or blender and pulse a couple of times. Beware the dust cloud when opening the food processor, and avoid breathing in salt dust. This step is optional but recommended because extra fine salt is gentler on the skin.
Melt your soap base and shea butter in a small microwave saucepan. To make this faster, you can shred or cube the soap bar.
Mix in your food coloring if using, and stir well.
Pour the mixture into your molds. Melt and pour salt soap will harden almost immediately, so work quickly.
Place the mold into the fridge to harden for about 20 to 30 minutes.
Once the soap bar feels cool, release it from the mold.