I have heard that in ancient times jewelry was not to be worn on Yom Kippur as part of the requirment to afflict the soul. Is this true, and if so what did it signify?

A. It was done so that one would not feel passionate toward his wife on Yom Kippur, since marital relations are forbidden on Yom Kippur. B. It signified the feeling that Yom Kippur is a day of justice and a man does not dress up, or wear jewlery on such a day. Also, there is a custom to dress in white i order to resemble angles which are clean of sins. Rabbi Ro'i Margalit