For a vast array of Buddhist Vajra please see~ http://drilbudorje.tripod.com/_Dorje.htm
where the clear defined thunderclap device can be understood as the same design on the Tibettan Sword pictured above and its technical transfer across the regions to the Sri Lankan Kastane pictured below.
The quilons appear vestigial
but they are not since they are not Quilons per se but form a part of the motif held in high esteem by Buddhist and Hindu alike and represent diamonds or thunderbolts and can be illustrated in an open aspect or closed as on the Kastane. [/B] The quilon aspect is purely Iconic as part of the Buddhist / Hindu display and revered by all...and are generally known as Vajra
It is my view and as part of this hypothesis that the closed form shuts out the possibility of this as a sword form when its true place is only ceremonial; Rank and Badge of Office / Court Sword only and that this usage is generally agreed upon. In addition since the Kastane was not a fighting weapon as outlined in several reports by notable Sri Lankan experts.
Placed for interest is another weapon form : The Mace from Tibet
another Icon for religious ceremony and not a battle weapon but with Vajra at each end. This adds weight to the fact that such iconic weaponry parts transferred across regional boundaries following the religious tide in that part of the world.
I therefor place this conclusion;[B]Thus by the simple method of comparison and detail presented herein; it can be seen that the Kastane is very much a home grown design from Buddhist and Hindu sources and not a European import. By the same proof there is no relationship except by accident of design between the Kastane and the Nimcha.
Ibrahiim al Balooshi.
See Below for comparison of Vajra and Kastane Architecture / Quilons.