Prong Setting Fail

Jim McIntosh has a great book called Wiresmithing and the combination of wire wrapping and prong setting is a perfect fit for stones that don't need wire covering their faces.  I got a gorgeous solar quartz slab from an eBay seller and thought if I was careful, it was the way to go.  I experimented with a strip of sterling gallery wire as the centre, creating a bail with the top end of it and it's a nice look.
Everything was going great until I decided the bottom prongs were too long and pried them up and shortened them.  When I hammered them down again, the stone broke at a fault line and a piece fell off.  E6000 glue put it back together again but you can see the split in the enlarged picture and I can't sell it with such an obvious patch.  But it's pretty and I guess it's mine.  And I still like the prong setting method.