Hi, 230 yr old yorkshire stone cottage that had an extension and significant refurb work done 1870.
I've ripped out the marble fireplace (not original) and open fire grate. Behind all that is the original stone and lintel in pretty good nick. The stones behind the hearth are blackened by soot, which is ok by me. However, the stone that surrounds the hearth on the outside wall is coated in white residues from the plaster (possibly lime??). Not sure how old the plaster is. Some early plaster is still there above the lintel (ie, horsehair mix etc) but there is also some more modern plaster presumbaly from when the marble fireplace was put in to the sides. Both have left white residual plaster on the stone. The trouble is I don't know how to get rid of that white residue. I tried a stiff, wet brush but to no avail. But I need to be careful as some of the stones are crumbly on the surface (I believe they will harden up after being exposed for a while?). Any suggestions as to how I clean the plaster off the stone?
I've ripped out the marble fireplace (not original) and open fire grate. Behind all that is the original stone and lintel in pretty good nick. The stones behind the hearth are blackened by soot, which is ok by me. However, the stone that surrounds the hearth on the outside wall is coated in white residues from the plaster (possibly lime??). Not sure how old the plaster is. Some early plaster is still there above the lintel (ie, horsehair mix etc) but there is also some more modern plaster presumbaly from when the marble fireplace was put in to the sides. Both have left white residual plaster on the stone. The trouble is I don't know how to get rid of that white residue. I tried a stiff, wet brush but to no avail. But I need to be careful as some of the stones are crumbly on the surface (I believe they will harden up after being exposed for a while?). Any suggestions as to how I clean the plaster off the stone?
