DO NOT SANDBLAST! We paid an experienced sandblaster to ruin our 100 year old fireplace. We gave him a brick to test and it was fine. We then scheduled the work and made an airtight plastic room around it. When he came I told him to test it on the side & if there was any pitting I didn't want to do it. Well he did it and it is all pitted and chunks of brick missing. He thought it looked beautiful and in fact, took pictures to put in his album to show potential customers. This happen 4 years ago and the fireplace is exactly as he left it because we don't know what to do. Keep the paint. If you really hate it, pay a faux painter to paint it terra cotta to look like brick again.