The celestial moon phase frame transforms a round mirror into a cosmic art piece, surrounding the central glass with eight distinct lunar phases crafted from luminous white mother-of-pearl set into a dense background of black onyx glass tiles. This design balances deep midnight black negative space with radiant, iridescent lunar silhouettes.

Begin by mounting a round mirror on an oversized circular wooden substrate. Trace eight evenly spaced circular moon phase outlines around the perimeter: new moon, waxing crescent, first quarter, waxing gibbous, full moon, waning gibbous, third quarter, and waning crescent. Cut shimmering white mother-of-pearl shell tiles and arrange them to fill each illuminated moon shape accurately. Fill the surrounding background space with tumbled black glass, black vitreous tiles, and tiny metallic gold star-shaped tesserae. Adhere all pieces firmly with black-tinted mortar. Apply pitch-black grout across the entire mosaic matrix, wiping the mother-of-pearl moons thoroughly clean to let the iridescent lunar cycle shine against the dark night sky.