Exposing brick chimney in kitchen

My 1916 house has a brick chimney (no fireplace) that runs through the corner of my kitchen and I was considering removing paneling/plaster to expose the brick.

I chiseled away a small test square and found the following

At this point I’ll probably just cut my losses and patch the hole (its hidden by the fridge anyway) but still curious as to what I’m looking at here.
In the basement there is clearly brick that runs up through the ceiling and into the kitchen. Does it transition to block? was the brick cemented over possibly? — thanks in advance