If it's big enough, try wrapping some of that nubby ACE bandage type stuff around the handle.
My hera marker is bone of some kind....lands I've had it for decades.....looks like a curved section cut from a large egg, and has a brownish striated/nubby section on one end, probably from where it was attached to whatever it came from. Sure wish I could remember what/where/why I got this so I could describe it better!
A hera marker makes a line for quilting that is a slight crease in the fabric....which of course, come out and doesn't leave a mark after the quilting design is done.
Jan in VA