You may well have seen brightly coloured bars of soap in stacks at some pricey shops – exuberantly fragranced and with elaborate lists of beneficial ingredients. But what’s the difference really between those soaps, and the ones here?

Basically, it’s where they start from. Traditional soap takes time. After the saponification process, it takes at least four weeks for the soap bars to cure, or season, before they can be used. The longer they are left, the better the lather. Castile soaps can be cured for many months.

However, this operation doesn’t scale very well. So in order to make production as simple and efficient as possible for a large, international chain, it’s far easier to mass produce base ingredients centrally, ship those out and have smaller local factories add the specified ingredients and then mould and cut the soaps for the customer in the shop.

The base here is what crafters know as “melt and pour” soap – produced in huge quantities, these bases can be melted in a microwave and you can add whatever you like, within reason. Once the soap has cooled and set, it can be used straight away.

Now, this is not to say that melt and pour soap is no good. Certainly you can do things with melt and pour that you can’t do with cold process soap. But it’s a different type of product. It doesn’t last as long as cold process soap and some people find it harsher on their skin.