marmoreal
Resembling marble or a marble statue; cold, smooth, white, etc.; marblelike.
literary
How many a night serene, shall I behold / Those vvarm attractive orbits, close inshrined / In ether, over vvhich Love's column rose / Marmoreal, trophied round vvith golden hair.
Made out of marble.
literary, obsolete
But each night as he stood on that high marble terrace with the curious urns and carven rail and looked off over that hushed sunset of beauty and unearthly immanance he felt the bondage of dream's tyrannous gods; for in no wise could he leave that lofty spot, or descend the wide marmoreal flights flung endlessly down to where those streets of elder witchery lay outspread and beckoning.
Where it comes from
From Latin marmoreus (“of, pertaining to, consisting of or made of marble; resembling marble; adorned with statues”) + English -al (suffix forming adjectives). Marmoreus is derived from marmor (“block or piece of marble; marble building or statue”) (from Ancient Greek μάρμᾰρος (mármăros, “marble”)) + -eus (suffix forming adjectives from nouns). By surface analysis, Latin marmor + -eal.
Adapted from the Wiktionary entry marmoreal (CC BY-SA 4.0).