Apparently from the same as drowr; properly, a pearl (from its sheen as rapidly turned); by analogy, pearl-stone, i.e. Mother-of-pearl or alabaster -- X white.
KJV: Where were white, green, and blue, hangings, fastened with cords of fine linen and purple to silver rings and pillars of marble: the beds were of gold and silver, upon a pavement of red, and blue, and white, and black, marble.
NASB: There were hangings of fine white and violet linen held by cords of fine purple linen on silver rings and marble columns, and couches of gold and silver on a mosaic pavement of porphyry, marble, mother-of-pearl and precious stones.