well I can tell you its made of Mahogany obsidian,and that I dont believe its a spear point.Double pointed pieces like that were generally ceremonial or wrapped with leather in the middle and used as a knife.Its difficult to tell but it may not be "authentic",(it does appear to be though)may be modern knapped?Pretty though!!
I keep coming back to stare at that piece!!!You should post it in the North American Indian section here,some folks there would really appreciate seeing it!