I'm actually surprised you recognized the ferrule for what it is as to my knowledge that's one of the most unique materials we've come up with- I've never seen an industrial or custom version. Both are a phenolic laminate like Micarta(TM) from scrap coffeebags, but the ferrule, and the handle on this knife:
are rolled, hidden-tang laminate- there's no "end grain" except at the end of the roll and where the handle's been strongly contoured. These handles were made with Columbian coffeebags, which seem to be sisal.
The other knife handle material are Indonesian coffeebags laid up in the more standard horizontal fashion. The spacer is actually leather that's fully sealed with acrylic. This customer wanted a large knife with an octagonal handle, but he wanted it handle-heavy, so we built it full-tang and were successful. The balance is immediately under the bolster/slot guard. The black handled knife in the picture is Brazilian coffeebag in a black-dyed resin.