Recently, I bought a complete set of OEM hydraulic lifters. They are all nice and shiny. They are all inside small plastic bottles and there is some oil inside each bottle. I looked inside all the lifters and they were all fine except for one of them. Please have a look at the following pictures:
All lifters are similar to picture B. There is clean oil inside. However, there are some tiny particles inside one of them (picture A). It looks as if the oil has been dried or something. They can be easily removed by hand.
Now my question is: What are they and what should I do? I'm worried about this one.
Thanks in advance.

