From today’s news page.
http://www.theage.com.au/national/35000 ... rom=age_sb
35,000-year-old axe head places Aboriginal ancestors at the cutting edge of technology
What makes this one different, besides its age, is that the edge was done by grinding, not flaking.
I have never heard of that with stone tools.
It is, of course, the way to sharpen a metal edge.