On 05/08/2020 13:48, Dave Liquorice wrote:
On Wed, 5 Aug 2020 10:25:32 +0000 (UTC), RJH wrote:

It's paint on an external brick wall, a skin of emulsion like paint on
top of rock hard masonry paint. It scratches off with a finger nail, but
is annoyingly hard to remove from this large area (about 60m2).

Pressure washer.

Good excuse to buy one!