Interesting piece, The faint zig zag etc markings were identical on the ricasso of this peace I had at one time. It is now in an established  private Sikh collection.
I presumed it was Sikh or Afghani from either, Punjab or NWF Border area or maybe even into Khyber or some such perhaps? 
it was about 22 inches  long , all wootz crystaline steel.  Strangly found bricked up in an old English famhouse wall during re building. Bit of wicca/earth magic I suppose.
I thought it seemed a very old piece.
Spiral