Anti-aliasing problem in cycles

The attached image shows some obvious aa issues along the curve. That is actually the reflection of a black plane in the glossy white edge of the knife blade. The actual black part of the blade is well aa’d. Model is a Bowie knife. I use 500 samples with standard settings. There was no change between about 200 and 500 so I don’t think increasing the samples will make any difference. The aliasing is so sharp it doesn’t seem to have been addressed at all (for the reflection). Any suggestions welcome.



What about increasing resolution and the tiles size?.