What is the difference between Parkerizing and Bluing (also spelled blueing)?
Parkerizing is a metal etching or phosphating process, which enhances the cosmetic appearance of metal. It provides a very durable finish that has extraordinary oil retention properties. PJ’s Gun and Metal Care Products carries the Radocy Parkerizing solution which produces a medium to dark gray finish (for more details see Parkerizing section below). Parkerizing generally provides a more durable finish than bluing because it allows for better oil retention and therefore is more abrasion resistant. Bluing (Blueing) is a controlled rusting process. It was originally used to camouflage a bright surface and to protect against rust. Special rusting mixtures are applied and allowed to rust, then they are brushed off and the steps are repeated until the desired colour is reached. In Europe this centuries old technique was first called russetting and then browning. Later on, a modified browning solution was introduced that resulted in a blackish-blue finish and as a result the name bluing cam
