Hi Katana,
Jens is 100% right, this appears to be a spear head from Sri Lanka.
In "Sinhala Weapons & Armour" by P.E.P. Deraniyagala (Journal of the Ceylon Branch of the Royal Asiatic Society", Part III, 1942, pp.117-118), similar is shown as a "...kuru Itale or kurukitale (elephant spear)" and apparantly the heads varied from 6" to as much as 48". These are described as having the median ridges raised into cutting edges which converge at the point of the spear. On the examples described there were apparantly straps downward to secure the head to the shaft (as seen on 19th century cavalry lances).
The brass, as Jens has noted also supports the southern India, Ceylon identification.
Your example is likely a ceremonial one from the 19th c. as the features are vestigial and the head lacks the securing straps that would be attached to the shaft. Apparantly the earlier forms actually had the median ridge expanded and sharpened and the downward projecting 'wings' at the base corresponded and were also sharpened.
Beautiful example!
and stuff from Sri Lanka seems pretty hard to find these days.
All the best,
Jim