Does anyone know what kind of finish this is?

[Cody Thompson]

This are interior walls in a property  we just purchased and are in the process of rehabbing. The house was originally built in 1960 so I don't know if this was popular at that time or sometime later. We are trying to find out the best/cost effective way to refinish or remove. 2 of the photos are of the fire place and it looks like this may be a panel that was placed over the original drywall and then finished. Any ideas would be greatly appreciated.

ated. Thanks! 

Sorry the photos were taken at night and in poor lighting.