In a large mixing bowl, add the baking soda, citric acid, white kaolin clay and cornstarch. Whisk dry ingredients together. Whisk in calendula flowers.

Add the coconut oil, polysorbate 80, and calendula essential oil. Mix ingredients thoroughly, until consistency feels like wet sand.

Mix in orange mica colorant, if desired.

Fill both sides of the mold with the mixture, press molds together and grind to remove excess mixture. Gently tap each side of the mold to release the bombs. Allow to dry a minimum of 24 hours.

Store in an airtight container until ready for use.