What to look for when cutting apart an oil filter?

I've got a new motor with a few hours break in time and one race night on it. I don't have any reason to believe that there is anything wrong but I cut the filter apart to see what's up. I didn't find any noticable large metal particles in the filter, just a few small particles of silicone. The oil I was using was VR1 Valvoline with Lucas break in additive. The only thing I have noticed is a small amount of shimmer in the oil. Almost like a very spread out metallic in a base coat paint. No huge particles. Is this something in the break in lube? Was my assembly cleanliness not as spotless as it could have been? Or should I start looking for a problem?