The high temp paint would be the product of choice here and all I have seen are black.

Because cinder block is not the most beautiful backdrop, anyway, and is there mostly to function as containment for a FIREplace, not a candle backdrop, I would construct some sort of removeable backdrop to slide into the fireplace and cover the cinder block up, altogether. You could use tileboard, which comes in many different colors, and caulk the seams to make a uniform finish. You could also install small hinges at the seams so that it folds up when you remove it for a REAL fire. Because it is removeable, you will not need to deal with the long-term consequences of changing the use of the fireplace: just remove it and ignite.

If you use non-fire rated paint, it will likely peel off and look horrible once the fireplace is used for fire, again. It will do so even if you subsequently re-paint it with fire-rated paint. The worst-case scenario is that it will burn off and the entire fireplace surface will catch on fire, but the flamable chemicals will likely (but not necessarily) have evaporated by then, so the more likely result is that it will just flake off. Any painted surface is only as strong as its weakest link, so if you have non fire-rated paint anywhere in the layers of paint, it will fail when put to the test and flake off.

[This message has been edited by Lawrence (edited September 14, 2002).]

If you use a high heat paint read the label carefully first. Most are designed to withstand high heat, not direct flame. e.g painting the outside of a grill, not the inside of a fireplace.