The stone lining should be made from the bottom upwards
Ornamental Stone Finishing of Arches and Doorways: Design Ideas and peculiar features of Decorative Finishing. : The Stone Lining Should Be Made From The Bottom Upwards
Quote from Article entitled Ornamental Stone Finishing of Arches and Doorways: Design Ideas and peculiar features of Decorative Finishing.:
After drying, apply an approximate outline of a finishing on it. There is no need in leaving flat edges. To make an arch look stylish and natural, slightly saw the edges of tile or handle them with nippers.
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