Mayonardo
You've got a very fine example of a Tortoiseshell Stockman there, it's an extremely attractive acrylic. Most of my stuff is in the GEC thread, but about durability of acrylic: I'd say it's good, but I never carry any pocket knife with keys or change-everything gets mucked up by that, bolsters suffer a lot and it's a hard-use I rule out

It's similar to Delrin but much less susceptible to cracking or chipping than Bone, no shrink like horn and no gas attack like Cell

If it scratches a strop will bring it back, so I rate it for durability.
1. Metal scales (but don't fancy them personally)
2. Micarta.
3. Stag. It endures dropping and regains shape from drying out or saturation, doesn't crack much.
4. Delrin/Acrylic
5.Bone
6. Horn/ Shell
7. MOP and that awful Green Snail Shell stuff a lot of people worship
Woods vary so much according to type and prep but Ebony, Blackwood, Coco, Zebra all very tough stuff that lasts a century or more.