Alternatives to Silk Fiber in Soap {an experiment – part 1}

Can you add different kinds of fibers, such as alpaca, cashmere, and bamboo silk to soap? I try those fibers and more in this cold process soap experiment!

bar of soap with unspun fiber and fresh plants

Several months ago, my daughter (an avid fiber/spinning enthusiast) saw me adding some Tussah silk fiber to soap, and wondered if other types of fiber could be used in handmade soap instead.

I hadn’t thought of that, but my curiosity was piqued!

She was specifically wondering about making cashmere soap or rose fiber soap, but I thought I’d test out every kind of fiber I could get my hands on.

These are the results of the first part of my experiment, testing 3 plant-based fibers and 7 animal fibers, plus a control bar with silk as a comparison.

Part two of this experiment will test more plant-based fibers (and there may be a part three), but first I need to make those soaps and let them cure for several months to observe. I’ll be sure to update here when those results are ready!

Main Takeaways

You can see more in the chart below, but the main lessons I took away from this experiment are:

  • It’s important to strain the lye solution, even if the fiber looks like it’s dissolved. Unstrained solutions tend to leave yellow spots in the soap. (But most don’t appear to be DOS – dreaded orange spots of rancidity – these were more reminiscent of scorched bits of milk in soap.)
  • Most of the soaps had a wonderful feel to the lather, but it’s hard to top the luxury of Silk Fiber in a soap. There was clearly something extra special about the soap made with Silk, though Cashmere was really close too! (Cashmere soap is definitely on my recipes-to-make list now.)
  • The animal fibers tested all had some level of silky feel. I would enjoy using a soap made with any of them.
  • For the plant-based fibers: Bamboo Top had a slightly nicer feel than Seacell Top and Pineapple Top, but nothing really impressive – and those last two just felt like regular soap. They may be good for label appeal, but unsure about actual benefits. More plant-based fiber experiments are in the cards for sure.
  • Common sense with allergens applies – label and disclose if you use an animal fiber in soap. I’m pretty sensitive to animal fur (my cats, dogs, goats, make me itchy when I pet them unless I wash my arms and hands immediately after), and none of these soaps bothered me. But certainly, there’s a potential.
soap batter being poured into soap mold

11 Fibers to Try in Soap (an experiment)

Here are the results from part one of my Fibers in Soap Experiment. In hindsight, I should’ve strained every one of the lye solutions through an even finer stainless steel mesh sieve than I used. I believe the yellow spots are related to my subpar straining efforts. 😊

Fiber TypeDissolves well?Yellow spots?FeelDid I
Cashmerefairly wellthreeexcellentyesundissolved bits turned
Baby Camelnot welltwovery niceyesmade brown flecks in
lye solution
Angoranot wellonevery niceyeswhite flecks in yellow
lye solution
Baby Alpacafairly wellseveralvery nicenoturns lye light yellow,
I should’ve strained
Yaknot wellnonevery niceyesbrown flecks, light
tan lye solution
Baby Llamanot welltwovery niceyesbrown flecks, light
tan lye solution
Kid Mohairfairly wellonevery nicenolight ash on cured soap
Bamboovery wellseveralnice-ishnovery light ash
Silkfairly welltwoexcellentnoclassic touch of luxury
Seacellnot completelymultiplenormalnoonly bar to smell “off”,
may be going rancid
Pineapplenot completelynonenormalnono negative issues

Natural Colorants


image of chart

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image of chart

Fibers Source

These are the fibers I purchased for my experiments:

Plant Based Fiber Top Sampler Pack, Vegan (Etsy)

Luxury Spinning Fiber Assortment, Animal (Etsy)

and my daughter is contributing a few pinches from her ever-growing stash. (She buys primarily from Etsy too.)

My Test Recipe

This is the recipe I used to make the test batches.

  • 2 oz (57g) olive oil (50%)
  • 1.25 oz (35 g) coconut oil (31%)
  • 0.25 oz (7 g) castor oil (6%)
  • 0.5 oz (14 g) refined shea butter (13%)
  • 1.13 oz (32 g) distilled water (2:1 water:lye)
  • 0.57 oz (16 g) lye (5% superfat)
  • abt 1/4 tsp fiber, snipped into fine pieces, stirred into hot lye solution

Many soapmakers enjoy felting their soaps with various types of roving, so this experiment seems to indicate that you could potentially include a bit of fiber inside the soap for added label appeal and extra silky feel. It’s certainly not for everyone, but may be a fun idea for some to experiment with further. 😊

collection of handmade soap ebooks

You may also enjoy my Handmade Natural Soaps eBook Collection. It contains:

  • Handmade Natural Soaps eBook
  • Natural Facial Soaps eBook
  • All-Natural Milk Soaps eBook
  • DIY Specialty Soaps eBook
  • Essential Oils In Soapmaking eBook
  • Quick Guide to Troubleshooting eBook
  • Printable Soap Additives Chart
  • Printable Essential Oils for Soapmaking Chart
  • Soapmaking Checklist to Keep You Organized
  • Reference List of Soapmaking Abbreviations
  • Helpful List of Soap Supplies & Resources


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Jan Berry is a writer, herbalist, soapmaker, and bestselling author of The Big Book of Homemade Products, Simple & Natural Soapmaking, and Easy Homemade Melt & Pour Soaps. She lives in the Blue Ridge Mountains with her family and a menagerie of animals, where she enjoys brainstorming creative things to make with the flowers and weeds that grow around her.