??????????? ?????? ????? ?????????? ???????????? ?????? ???????? ??????, ??????? ?????????? ???????? ?? ????????? ??????? ? ?????????? ??? ???? ???????????? ?????????? (???.).??? ?? — ???????????? ???????????? ?????????? ??? ??????? ?????????? ??? ??The lesser the concentration of such trace features, the “whiter” or even more colourless the