Hard olive-oil soap

What it is

A solid, scented soap made by saponifying olive and laurel oil with soda from coastal plants (al-qali) and lime. The first modern bar soap, exported throughout the Mediterranean.

What it led to

• the soap industries of Castile, Marseille and Venice (Castile soap)
• personal hygiene and textile cleaning in the cities
• the concepts of alkali and saponification in chemistry

Built on

• Roman and Gallic soft soaps
• olive cultivation

Made possible

• Isolation and characterisation of glycerol1779 (aislamiento de Scheele) / 1823 (caracterización de Chevreul)
• Shampooing: steam bath with head massage (origin of shampoo)1814
• Mercerisation of cotton1844
• Self-bleaching laundry detergent (Persil)1907
• Marseille soap
• Castile soap

Links

Sources✓ verified 2026-09-23

• https://en.wikipedia.org/wiki/Aleppo_soap
• https://en.wikipedia.org/wiki/Nabulsi_soap
• http://www.history-science-technology.com/notes/notes5.html