Peppermint Foot Soak
1) A large mixing bowl
2) Kitchen scales
3) Lidded pail (if making for decanting later) or make in a suitable jar/wide-necked bottle
4) A suitable jar or wide-necked bottle to decant into if necessary
Measure out the Sea salt and Epsom salts into the tub or large wide-necked bottle/jar in a ratio of 2:1 (2 parts sea salt to 1 part epsom salts) and mix together thoroughly.
Calculating the total weight of the mixture, measure out 2% in weight of Peppermint Essential Oil and mix this with just enough cornstarch (or tapioca starch) to make a dry powder, then add to the mixture and stir in thoroughly. (It is worth remembering that the volume and weight of epsom salts and coarse sea salt correspond quite closely, so 200g of the mixture will also fill nearly exactly 200ml in volume, so for every 100g of mixture, use 2ml of essential oil/s or fragrance).
If adding colour, mix a few drops of liquid dye (blue or green are appropriate) into just enough cornstarch (or tapioca starch) to make a dry powder and add to the mixture a little at a time, stirring throughout, until the desired depth of colour is achieved (do not overcolour as the dye will colour the water when used).
Leave the mixture to stand, covered, for at least a day for the fragrance to thoroughly permeate the salts.
Using a funnel or similar utensil, you can now decant a little at a time into a suitable bottle or scoop into a jar for using as you please.
For adding a little effervescence, mix together a little sodium bicarbonate and granular citric acid (50/50) and replace some of the sea salt weight-for-weight.