Thread: How can you tell if it's bone?

I've got a razor I'm restoring that has what look to be bone scales, but I'm not entirely sure. How can you tell/test for bone?

Bone usually has pores from blood vessels.

One way to recognize bone is to grasp each end with pliers and twist until it breaks. A synthetic material will crack or shatter, while bone will splinter in a spiral fracture with the most pleasing crunchy sounds.

lol.


Seriously, the thing about pores from blood vessels is okay, but that can be hard to spot depending on how it was finished.

Try that, but also remember that bone is made up of fibers of calcium and phosphorus, so it will have a grain to it. This can also be hard to spot depending on the finish, but will probably be a lot more obvious if you get some good light and look in between the scales to see what the unfinished texture looks like.

Ultimately, even the best synthetic bone handles are still plastic, and when you hold them, they won't feel like something that was once living the way bone will.

You can hot pin test it too. Get a pin red hot & touch it to an inconspicuous area (inside the scales). If it melts, it's synthetic. If not, it's either bone or ivory. Then you need to look at the structure to tell these two apart. As mentioned, bone will have pores. If you've got a loupe or something that will make them easier to see.

Give it a light sand. Won't tell you if its bone or ivory but the celluloid smell of camphor can be eliminated.
Bone will likely look more porous than ivory under magnification also.

The pores in bone scales are usually most evident at the top and bottom ends - in old handles the pores get filled with dirt, and because they were once the site of blood vessels they penetrate the bone and anything but the most superficial soiling is nigh impossible to clean or sand away. Bone also often has blotchy discolourations.

If the scales don't fail the pin test, they could be ivory or bone. Ivory has a grain pattern running along it, and another (often very hard to see) pattern running at right angles. Ivory is usually a more regular colour than bone, and it doesn't have the grime-filled pores in it like bone.

So, if its old, a bit soiled and has little dark dots near the pivot and wedge end it is probably bone. It's usually quite thin too, and most I have seen have thin metal (lead? pewter?) wedges. Same goes for ivory, however.

Other than that, what Ben said.

Regards,
Neil

Originally Posted by Neil Miller

The pores in bone scales are usually most evident at the top and bottom ends - in old handles the pores get filled with dirt, and because they were once the site of blood vessels they penetrate the bone and anything but the most superficial soiling is nigh impossible to clean or sand away.

Are there no awesome tricks for cleaning discoloration from bone scales?
Also, once you have bone cleaned (as much as you can) and sanded smooth, should one finish it with some sort of sealant or leave it natural? Seems like finishing would prevent further soiling, but would take away from the feel bone has...

Originally Posted by ben.mid

You can hot pin test it too. Get a pin red hot & touch it to an inconspicuous area (inside the scales). If it melts, it's synthetic. If not, it's either bone or ivory. Then you need to look at the structure to tell these two apart. As mentioned, bone will have pores. If you've got a loupe or something that will make them easier to see.

Good tip, but please don't try this if you even think you may have celluloid scales. Celluloid is highly flammable!

I'll try for the pic, but I'm having camera issues at the moment.

Originally Posted by Casey302

Good tip, but please don't try this if you even think you may have celluloid scales. Celluloid is highly flammable!

Yes, it is.
Here's the little used "Flame Test" I'm not sure a hot pin can induce it though!


YouTube - Celluloid Scales Flame Testing