What is Cold Process Soap?

A traditional craft with real skin benefits

If you’ve ever picked up one of my bars and wondered “what exactly is cold process soap?”—you’re not alone! It’s one of the most common questions I get, and I love explaining it because this method is at the heart of what makes Fog & Fireflies so special.

🌿 What is cold process soap?

Cold process is the traditional way of making soap—from scratch. It’s a chemical reaction called saponification that happens when you mix oils or butters with a lye solution (sodium hydroxide and liquid). Over time, the mixture thickens, is poured into molds, and then cured for several weeks. The result? A gentle, long-lasting bar of soap that cleanses without stripping your skin.

Unlike melt-and-pour or mass-produced soap, cold process allows complete control over every ingredient—from the oils and butters, to the scents, to the colors.

💧 Why does cold process soap matter?

At Fog & Fireflies, I make every batch by hand using the cold process method because it means I can:

• Use high-quality, skin-loving oils like olive, coconut, avocado, and shea

• Infuse each bar with therapeutic-grade essential oils for natural scent and benefits

• Color soaps with only natural clays, charcoal, and botanicals—no micas or synthetic dyes

• Avoid detergents, sulfates, and preservatives found in many commercial soaps

• Create bars that are rich in natural glycerin, which attracts moisture and leaves your skin feeling soft, not dry

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Cold process soap is more than just “fancy” soap—it’s real skincare, rooted in tradition, made with purpose.

🖐️ Small batch, big love

Each bar you buy from Fog & Fireflies has been poured, cut, and cured with care. It’s part science, part art, and 100% handmade. I love this slow process because it lets me stay connected—to the ingredients, to the earth, and to all of you who’ve supported this dream.

Thanks for following along, and for letting my little soaps be a part of your daily rituals. If you haven’t tried cold process soap yet, I hope you’ll feel the difference.

With gratitude and lather,

Darlene

Fog & Fireflies