HERE ARE SOME OF THE ANSWERS:
it’s a bone for a glass dog. they were bred in the early 19th century; but short life span made it impossible to keep them viable.
A serving knife rest, so your lovely lace tablecloth will not be stained.

Congrats on keeping the comments clean everyone!
Baby dumbbell. No one likes a weak baby.
It’s a knife rest. These are not only for the carving knife, but one is at each place setting for resting the table knife after it’s used. It is NOT for the butter knife. The butter knife remains across the bread plate.

My grandmother had two. I don’t know about her background, buy she had many instruments that showed she entertained often.. I have a set of 12 salt cellars with tiny crystal spoons to sift the salt from the cellars over individual food. We used them at Thanksgiving and holiday dinners.
Today none of my children know how to “play” fancy meals.

Sad tradition. If it won’t get washed in a dishwasher, they won’t keep them in their house.
No talking- no experiences other than food from a paper bag.
To lay you knife on after you cut your meat so you don’t mess up your tablecloth
Knife rest. Kind of like a chopstick rest

Dirty knife rest keeps table cloth clean.
Lol I have one from my mom, never knew what it was for. Now I do! Thanks
Wow!! Thank you for insights!! So cool to have this group!! The knife rests sure are beautiful!!
Have one just like this. Resting of the carving knife, if you only have one.

I’ve never seen one, they are beautiful!
Wow! I thought I knew different types of serving utensils, but I didn’t know this one. Thank you for sharing!
We used t have one like that, my Mom and my Grandma’s. Salt roller maybe?

I have a set of them
It’s to set a knife holder.
A knife rest is a small, often decorative, object used to keep the blade of a knife from touching the surface of a table or countertop when it’s not in use. They come in various shapes and materials, ranging from simple metal designs to more ornate versions made of silver, porcelain, or other materials. They can add a touch of elegance to a dining table while also serving a practical purpose.