[pcabc]

US sector breadth charts:
           
           
           
   

I think the US Materials sector is worth a look, as although not the strongest sector the pullback has been minor, rather it just takes back a shart gain the previous day.  If you take out Wednesday and Thursday's data there is a climb that continues to Friday, with the only really notable thing being a massive volume spike.
   

I don't think this results from precious metal miners as thier charts are quite a different shape in recent months, both with significant pullbacks that we do not see in the US materials sector..