Top three mortar joints deteriorated, the rest OK.
Owner stated that they remodeled the fireplace face this summer after deciding to put it on the market.
My theory is that the chimney was originally too low and didn’t draw well, so there was some smoke damage on the face of the old fireplace and mantle. At some point one cold winter they had a new fireplace installed and the installer said “hey, chimney’s too low, that’s why it smokes!” so they extended the chimney. During the winter.
The mortar froze before it cured fully and so was weak and subject to accelerated weathering. That’s my theory, anyway.
Thought I’d add the bighorn lambes and ewes. They ran accross the road in front of me on the way there.