This might be an interesting fact for you silk wearing ladies and gentlemen:
Silk should not be laundered in ordinary modern detergent! The enzymes are no good for silk fabric.
Maybe everyone else knew this already - but nobody told me until the age of 40.
Instead, an oil based old fashioned soap should be used. Savon de Marseilles is one example, but there are others. They can be made of olive or palm oil, as long as they only contain traditional ingredients.
Now, the useful thing about this type of soap is that it is not only natural but also multi-purpose. When I travel I bring a small bar and use it on my clothes (any material), myself, even my hair. No need to carry around lots of water in the shape of shower gels or shampoo. Soap is compact, light and hand luggage friendly.
Some people dislike soap because the box tends to become a bit messy. But instead I keep it in a small mesh bag, which I hang and let dry while I do other morning chores. Another way to lighten my backpack with a few grams.
Sorry if this post is off-topic, as it is no longer an answer to Desleigh's question. But I thought it might be useful to someone planning the Camino.