Here’s a little bit of info about vinyl records courtesy of Wikipedia:
The sound quality and durability of vinyl records is highly dependent on the quality of the vinyl. During the early 1970s, as a cost-cutting move towards use of lightweight, flexible vinyl pressings, much of the industry adopted a technique of reducing the thickness and quality of vinyl used in mass-market manufacturing, marketed by RCA Victor as the “Dynaflex” (125 g) process, considered inferior by most record collectors.[44] Most vinyl records are pressed from a mix of 70% virgin and 30% recycled vinyl.
New “virgin” or “heavy/heavyweight” (180–220 g) vinyl is commonly used for modern “audiophile” vinyl releases in all genres. Many collectors prefer to have heavyweight vinyl albums, and they have been reported to have a better sound than normal vinyl as they have a higher tolerance against deformation caused by normal play.[45] 180 g vinyl is more expensive to produce only because it uses more vinyl. Manufacturing processes are identical regardless of weight. In fact, pressing lightweight records requires more care. An exception is the propensity of 200 g pressings to be slightly more prone to “non-fill”, where the vinyl biscuit does not sufficiently fill a deep groove during pressing (percussion or vocal amplitude changes are the usual locations of these artifacts). This flaw causes a grinding or scratching sound at the non-fill point.
Since most vinyl records contain up to 30% recycled vinyl, impurities can accumulate in the record and cause even a brand-new record to have audio artifacts such as clicks and pops. Virgin vinyl means that the album is not from recycled plastic, and will theoretically be devoid of these impurities. In practice, this depends on the manufacturer’s quality control.
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