A Hindu deity is generally identified by ornaments, color of dress, weapons and instruments mostly musical. The same deity may have more than one form and in dhyana shloka (verses uttered in meditation before worship), various ornaments are referred to. Anklets, bangles, armlets, a gold chain or pearl necklace, rings and crowns are commonly found.
The same deity can appear in different forms – Nataraja (the dancing Shiva), Ardhanarishwara (an image of Shiva representing both male and female principles), Bhikshatana (the form of Shiva carrying a begging bowl), and so on.
Some deities have one or more identifying ornaments. For instance, Vishnu wears the famous jewel Kaustubha on his breast. This gem emerged from the milky ocean when it was being churned.
Vaijayanti is Vishnu’s necklace, made of five gems set together.
Shiva has snakes as his ornaments. Nala and Kubera, two celestial beings, are said to have taken the form of the two earrings of Shiva.
Shiva is also described as wearing earrings known as Kundala (pendant) in the form of Makara (fish).
Adishesha, the serpent, is Shiva’s anklet.
Goddess Parvati wears a string of crystals and rudrakshas called sphatika shamala. She also wears tatanka – ear ornaments.
Goddess Kali has a string of human skulls as her necklace. She wears wild elephants as ear ornaments.
Goddess Durga wears the nose ornament. Karnikara (golden flowers) are also used as ear ornaments.
Dhyana Slokas of deities describe the special ornaments worn by gods and goddesses.
Adi Shankaracharya writes in his Saundarya Lahari that this tatanka of Durga, the Mother Goddess, saved him when he consumed the deadly poison. He celebrates the nose stud of the Mother Goddess just as Lalita Sahasranama does.
It is said that the diamond nose-stud of the Mother Goddess Kanyakumari at the Kanyakumari Temple at the southernmost tip of India served as the lighthouse for ships voyaging in the eastern seas – such was its brilliance.
Vedic gods are described as wearing gold ornaments, carrying weapons and traveling in golden chariots.
To this day the custom of wearing abharana on deities persists and in temples in South India the deities are fully decorated with dazzling ornaments on festive occasions.
Source - Encyclopedia of Hinduism - Volume 1 - page 2 and 3.