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You will need 24 Fire Resistant Cinder block caps
2 bags of red lava rock
small bag of mortar
4 cinder block caps (for the inner square)
prepare the area that you're installing your new firepit by ensuring the ground is level.

Lay down 8 fire resistant caps in a square (they'll look the top as pictured here

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Next, stand the blocks on their sides in the center of the blocks to form a square.

Mix the mortar according to the directions on the bag and mortar these blocks in place.

At the edge of the inner square place one block on it's side facing inwards.

Apply mortar to the top of the inner square blocks and then seat the remaining caps on top. line the bottom with lava rocks.