If the white detritus seems to be a build up of very small white dust and flakes it is worn vinyl - yes, from the record. If you magnify it, then watch a tiny drop of acetone when dripped on it, you'll see it melt together.
The vinyl comes up in little "rods" when you play a record, and without magnification, it looks like pretty fine dust without color. In such small pieces the vinyl is not opaque, you can really not see any pigment. This is the way any dyed material that is not super dense in dye appears when you get it thin enough.
In my experience heavily profiled stylus tips seem to pick up more vinyl dust and flakes. In any case, if you imagine the miles of groove that the stylus travels it is pretty amazing, and this represents a small amount of vinyl relative to that tracing distance.
The vinyl comes up in little "rods" when you play a record, and without magnification, it looks like pretty fine dust without color. In such small pieces the vinyl is not opaque, you can really not see any pigment. This is the way any dyed material that is not super dense in dye appears when you get it thin enough.
In my experience heavily profiled stylus tips seem to pick up more vinyl dust and flakes. In any case, if you imagine the miles of groove that the stylus travels it is pretty amazing, and this represents a small amount of vinyl relative to that tracing distance.