Then its unifacial,I was asking so i could rule out another possible genus that it could be.Yours seems to fit the chararcteristics of Pachyseris speciosa.
P.speciosa- "Colonies are unifacial laminae, usually horizontal, but may develop upright ridges or columns. They commonly form stands several metres across. More than one row of corallites may occur between ridges. Columellae are absent."