You can check the Silvergen site. Actually Natural Immunogenics did some 
testing on batches from the Silvergen SG6 and 7 and both were rated excellent 
quality by the Natural Immunogenics lab. I wouldn't be concerned at all how 
small your particles are, as they are indeed very small. If we were talking 
about the brown CS from who knows where in Mexico THEN I would be concerned.
 
Steve