Saponified oils, superfat, essential oil versus fragrance oil, and which words on a label actually tell you something.

Soap labels look opaque until you know that most of the list describes what the oils became, not what went into the pot.

“Saponified oils of…” and “sodium olivate”

Both mean the same thing: the oil has reacted with lye and is now soap. Sodium olivate is saponified olive oil, sodium cocoate is coconut oil, sodium palmate is palm. Seeing lye (sodium hydroxide) on the list is normal — none of it remains in a finished, cured bar.

Superfat

Makers usually leave a few per cent of oil unsaponified so the bar is not stripping. That is the superfat. A higher superfat feels more conditioning and lathers a little less.

Essential oil or fragrance oil

Essential oils are distilled from plants; fragrance oils are blended. Essential oils limit the palette — there is no essential oil of “fresh linen” — and some fade in cold process. Fragrance oils hold scent longer and allow scents that do not exist in nature. Neither is automatically gentler; both can irritate sensitive skin.

Colourants

Clays, charcoal, madder root and indigo are natural. Micas are mineral pigments, usually synthetic for consistency. Either can be fine; what matters is that the label says which.

What a short list tells you

A bar with four oils, water, lye, one scent and one colourant is easy to reason about if something irritates your skin. That is the practical argument for buying from makers who publish the exact list per batch.