Hindu married women usually wear shankha (white bangles made of conch shell), pala (red bangles made of red coral), loha (iron bangles) and sindoor (vermilion). Many saints belonging to Sanatan Hindu society also wear sindoor on their forehead. In some places of India many male persons of this society wear sindoor on the occasion of particular rituals and festivals. Besides, shankha and sindoor are used in many rituals and religious celebrations. Three reasons (social, spiritual, and scientific) are identified behind the uses of these things. I’ll try to discuss these in brief.
In Hindu society, marriages are held follohwing the calendar time or according to the sacred time prescribed by a Hindu priest. Traditionally, women of the bride’s residence perform some pre-wedding rituals. Putting shankha-pala into her both hands is one of them. The mother of the bride presents the shankha and the pala to the bride in the morning of her marriage day. Sindoor is smeared on the parting of the bride’s hair by the bridegroom at a particular time during the marriage ceremony and the iron bangles are gifted usually by the bride’s mother-in-law to her when she enters her husband’s residence. Shankha, pala, loha and sindoor- all these are symbols of marriage for a Hindu woman. After the death of her husband she stops the usage of these things. If a Bengali Hindu married woman does not use these things, she is criticized in her society. There are some superstitions regarding these in some groups of the Hindu society. For example, if shankha or pala of a woman break within one year of her marriage, it is considered to be a bad omen for her conjugal life. Spiritually, the white colour of shankha, the red colour of sindoor and the black colour of iron stand for sattva, rajo or tejas and tamo respectively. These three gunas (qualities) are very important in Hinduism. When a woman smears sindoor on the parting of her hair, she does it upwards. It is also symbolic. Smearing it upwards, she actually prays long lives for her husband and herself. Besides social and spiritual reasons, some researchers have given scientific explanations regarding the usage of shankha, pala, loha and sindoor. They have explained that a woman loses three important things of her body at the time of her menstruation. These are calcium, iron and mercury. So, a woman can regain those elements wearing Shankha, pala, loha and sindoor.
Nothing is groundless in Hinduism. Like many other things, the usage of shankha, pala, loha and sindoor has also multi-dimensional logic in Hindu society. So, everyone belonging to this society should respect these auspicious things.