I've had a reclaimed yorkshire stone coping stone installed on a dwarf wall just by my front door. It's covered in some sort of bitumen and remnants of what looks like green pain. I'm guessing it previously resided on a roof.
As you can hopefully see in the photos a layer of it is flaking off in places but seem well attached in others.
So I'm thinking of knocking of the remaining bits that are flakey, cleaning the bitumen of the remaining bits and then blending the two levels together by somehow abrasivly removing the lip with a scraper or wire brush drill attachment? Then maybe sealing it to stop further freeze thou damage.
I know it sounds rough but its no oil painting at the moment. I actually quite like that its a bit rustic but not that rustic.
any advise would be welcome.