To make recycling more efficient, the Tracer Based Sorting (TBS) system uses a two-photon Anti-Stokes process to mark plastics according to specification, manufacturer/brand and application. The Tracer Based Sorting then uses colour-coding to do the triage, having proven to work even in the dusty ambiance of a PVC sorting facility. The system can also separate glass fibre-reinforced plastics (GFRP) from their polymer counterparts.