The next step in the fireplace construction was the firebox.  I used the same egg carton brick technique as I did for the mantel brick but in a slightly larger size and without rounding the edges.  I wanted it to look like a different type of material.  I didn't line the upper inside edge with bricks.  I had cut the firebox to be taller than the front opening to give the illusion of the firebox opening up into the flue above.

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I've found the best way to get a realistic look to the bricks is to do multiple layers of color.  I started with a thin coat of antique white.  I then brushed on a thin coat of light brown mixed with grey.  Over that I painted a layer of glaze mixed with dark grey.  It looks dark and mottled, but the grout will even out the color overall.

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I used Andi Mini Brick and Stone Mortar Mix (the same grout used for the foundation) to finish off the look.  I scored the lines between the bricks with an awl to add more definition.

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I will blacken the logs and add other touches to lend to the realism when I install the fire lighting.  I will also be adding a hearth, though I haven't decided on a finish for that just yet.

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