T514.  Bronze (I believe) arrowhead or possibly a spearhear.  7.5 cm on the edge and 14.8 cm overall.  I can’t tell you much about this piece: only that it came out of a Japanese sword and fittings collection.  I don’t know for a fact that it is Japanese; nor do I know it is old (could be both but I don’t know).  Maybe it is worth $100.