A wet hand holds a sudsy soap bar with black charcoal swirls

An Insider's Look at Soapmaking

We're giving you an in-depth look at every step of the process that turns lye, natural plant oils and botanicals into an ultra-moisturizing Spinster Sisters soap bar.

Stage One: Saponification

Our soap is crafted in 35-pound batches that produce up to 114 bars. We use the cold process soap method which is formulated to create a high-fat, moisturizing bar.

To start a batch, we dispense liquid lye from a large vat. The lye is then blended into a base of plant oils, exfoliants, scent and colorants.

Lye is portioned then poured into a purple mixture of oils

Emulsification with a blender creates a milky-looking liquid that is then poured into a mold. Saponification has begun! The alkalinity of the lye changes the chemical structure of the mixture to create soap. No lye remains in a finished soap bar. 

The soap mixture hardens very quickly, but there is just enough time to pour a second color over the soap in the mold to create swirling designs in the soap bars.

A large vat of soap is poured into a mold

Stage Two: Cure & Cut

The soap rests in the mold for up to 48 hours to allow it to heat up and pass through the gel phase. After the soap cools and is firm enough to handle, it is cut and divided into bars.

Soap is cut into bars by a Spinster Sisters employee in a white coat

Fresh soap bars are cured on the rack for 4-6 weeks. During this time, the soap hardens and the soap becomes milder as water evaporates from the bar and the saponification process completes.

The soap is then boxed and ready to be lathered up and enjoyed!

Soap dries on a rack and is placed into boxes

Stage Three: The Finished Bar

The luxurious ingredients we use provide our finished Bath Soap with a rich lather that is gloriously moisturizing for skin. It is vegan, biodegradable, long-lasting and sulfate free.

A Eucalyptus Lime soap bar surrounded by fresh limes

Shop our entire Bath Soap collection to try our latest scents.

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