Exodus 38:8 And he made the laver of brass, and the foot of it of brass, of the lookingglasses of the women assembling, which assembled at the door of the tabernacle of the congregation. - Free Bible Online

      8. laver of brass . . . of the looking glasses of the women--The word mirrors should have been used, as those implements, usually round, inserted into a handle of wood, stone, or metal, were made of brass, silver, or bronze, highly polished [WILKINSON]. It was customary for the Egyptian women to carry mirrors with them to the temples; and whether by taking the looking glasses of the Hebrew women Moses designed to put it out of their power to follow a similar practice at the tabernacle, or whether the supply of brass from other sources in the camp was exhausted, it is interesting to learn how zealously and to a vast extent they surrendered those valued accompaniments of the female toilet.
      of the women assembling . . . at the door--not priestesses but women of pious character and influence, who frequented the courts of the sacred building (Lu 2:37), and whose parting with their mirrors, like the cutting the hair of the Nazarites, was their renouncing the world for a season [HENGSTENBERG].

JFB.