Often, people talk about “old-fashioned horse-hair plaster,” but the binding agent in old plaster walls was more commonly cattle hair. -searshomes.org
![enter image description here](https://i.stack.imgur.com/ikzMY.jpg)
I am reasonably sure it's not asbestos.
Nobody can tell you whether or not that is ACM (asbestos containing material) by the pictures. You have to send it to a lab to know for sure.
Does it look like other ACM I have encountered? Yes
Will it hurt you if you wet it, bag it, and throw it away? No
Could it hurt you if you keep it laying around on your desk taking pictures of it and handling it? Probably not, but you should throw it away and stop stressing out
It takes time (think repeated/prolonged occupational exposure) for adverse health effects due to asbestos exposure.
Dust would be your biggest concern, especially for children. It is in what is called a friable state, meaning easily becomes airborne and inhaled. As a precaution, in the absence of lab results, it should be handled wet, like moistened with a water spray and mopped up while wearing a particulate respirator (a regular dust mask is not recommended). Alternatively, it can be vacuumed using a HEPA filter with the aforementioned respirators. Wear disposable coveralls (we use Tyvek™) and bag those and dispose as well. In the U.S.A., for confirmed ACM, this activity is regulated and may only be performed by specially trained and licensed personnel due to likelihood of repeated occupational exposure, and the waste is treated as hazardous.
Best Answer
if its from the 50's the chances are very high. however, it is region specific often. if you are located in the eastern us or canada, there is a very good chance of it. if you are worried about it, you can remove a small sample and take it to a local health lab or college chemistry lab and have it tested.