C.G. Virgin vinyl is the purist, most unadulterated form of vinyl. Virgin vinyl, in it's raw form, has very little in the way of impurities. Although it is manufactured in Europe, Asia and the U.S., most audiophile record manufacturers have records pressed by JVC. JVC does in fact have their own vinyl manufacturing facilities and has always been known in the industry to have basically set the standard for quality.
During the manufacturing process, there are often "mispressings". Instead of simply discarding these bad pressings, the record manufacturer will reclaim the vinyl by remelting. Often the paper labels and glue used to affix the labels, gets "reclaimed" also. During the remelting process, the vinyl is elevated to a high enough temperature to "burn off" the paper, but the ash and other impurities remain in the raw vinyl.
This is probably one of the most significant contributions to record surface noise. Virgin vinyls have certain specific criteria established for the percentage of impurities permitted in the vinyl's raw form. JVCs criteria happens to be some of the the most tightly controlled and some of the most stringent in the industry. The major European manufacturers such as Telarc and D.G. also maintain quality criteria, but the ears will tell you that they are simply not as quiet as some of the JVC pressings.
Audiophile vinyl recording manufacturers will also have their own criteria established. They will require a specific quality level in not only the raw material, but also in the finished product by means of surface noise characteristics measured in decibels. Finished surface hardness is also an important consideration for the manufacturer as this will have an overall effect on the actual longevity of the finished product, and also minimizing degradation of sound quality as wear occurs.
And to answer your final question, Yes, if you can find pressings on high quality vinyl, try them. You can be assured they will be somewhat quieter, revealing a higher level of detail. But also, don't make the mistake of thinking that just because it is on quality vinyl that it is going to sound better. The pressing of the record is also an extremely important factor in producing a high quality recording.
Hope this helps, happy listening.