So it looks like there is plenty of pictoral and statuaary evidence for embellishment in 12th century France. This reenactor (I’m not sure if she is a SCAdian) has compiled a lot of images with citations in her project diary: [Link] (French)
Another page from a French reenactor, but they are looking specifically at the embroidery, and using literary sources as references: [Link] (French)
You can see the section of the Grove Encyclopedia of Materials and Techniques in Art on Google Books – it talks about 12th century French ecclediastical embroidery (linen “entirely covered” with “couched gold thread and silk embroidery.” It’s section on beadwork isn’t so robust when it comes to our period: [Link]
Here’s the section of Stefan’s Florilegium on beadwork embroidery: [Link]
This book was cited on a very general article about medieval beadwork, but it looks promising. Your local library should be able to ILL it for you.
A pictorial history of embroidery, by Marie Schuette and Sigrid Muller-Christensen. New York: Praeger, 1964. [Link]
Beadwork was clearly a thing in other countries in the 12th century – there seem to be a lot of examples from Spain and Germany.
I hope this helps! Let me know if you need more. 🙂