I spent several days at the Ray during round-up and while it wasn't the most productive i was happy with what i found.  The first day i picked a spot up under a tree i had worked the week before and didn't find anything specimen worthy but i did find some fluorescent orange material (i believe it is apatite?) but even the mud had an eerie glow in some spots some i am not sure exactly what it is. 

The rest of the time at the ray i spent digging with Gene, we hiked up past the second pit and ventured right about 50 yds to the old tailings where we started to dig. 

Here is a link to the best piece i found, it was about six feet down, past the first boulder layer and near the bottom of the gravel layer that is about a foot to two feet thick.
http://imgur.com/a/sZGyC

I've never been up to mas celo, if you're looking to dig this weekend, there is a group heading to burgin quartz mine.