Mistaken Identity - Shiva Trident
Two Shiva sculptures from the Tamil Chola Dynasty from South India almost a thousand years old can easily be mistaken for the khanda emblem at first glance, or more closely the Aad Chand emblem worn by members of the Nihang sect.
The Chola Dynasty Shiva Tridents
The Chola Dynasty existed from 300 B.C. to the 13th century and died out almost 400 years before the birth of Sikhism.
The two ancient Chola bronze sculptures are almost a thousand years old. Both sculptures feature the Hindu god Shiva as Ardhanari (half-woman) leaning against his bull Nandi. Behind Shiva is a large depiction of a trident comprised of one curved outer semi-circular arms gradually tapering to points and a central vertical multi-edged sword like element.
The trident or trishula is a standard weapon appearing in depictions of the Hindu god Shiva. The word trishula means ‘three spear’ in Sanskrit and Pali indicating that it is a three pronged weapon. The three points of the trident have various meanings and significance within various Hindu religious schools of thought. The trishula of Shiva is said to destroy the three worlds: the physical world, the world of the forefathers and the world of the mind. The three worlds are supposed to be destroyed by Shiva into a single existence of bliss. 
Experts at both the Cleveland Museum and The British Museum which hold these two sculptures have identified the large weapon appearing behind Shiva as a trishula trident. The outer circular prongs of the trident are once continuous curved piece that tapers to a point and bears a strong resemblance to the Chandra crescent moon symbol that is also associated with the Shiva deity. The central vertical point of the spear has multiple sharp edges that suggest it a flat broad khanda like sword. The broad khanda like sword is a very ancient weapon, images of which have been found on Indian pottery dating to 1500 B.C.  and is also sometimes seen in depictions of Shiva.
A very rare surviving Chola dynasty sword. It has a shape that is similar to the central vertical element of the trident depicted in the two Chola Shiva sculptures.
Depictions of the Shiva trident as found in these two Chola era sculptures are extremely rare and unusual. Most depictions of Shiva’s trident usually have a shape where the two outer sharp points curve outwards, although rarer depictions of a trident with a convex shape do exist.
Given the extreme rarity of the shapes depicted in these two Chola sculptures, the end of the Chola Empire almost 400 years before the birth of Sikhism, the physical remoteness between Punjab and South India, the chances of influence on the Sikhs or the Nihang sect in the development of their religious symbols seems remote. No documented evidence suggesting any historic link has been found.
1. Wikipedia, http://en.wikipedia.org/wiki/Trishula
2. Wikipedia, http://en.wikipedia.org/wiki/Khanda_(sword)