it is surface hardening - and it is useful. It just isn’t work hardening. I like argentium too - and there is now an argentium metal clay available. Very new. Long in production.
I am adding LOS on a lot of brass & silver pieces and get fine highlights by using a large 6" brass wire wheel or small 1" handheld brass wheels…I do like the finish this gives me which may not be to your liking…very bright but not mirror…there are methods using small fiber wheels with various cmpds also.
Renee - There are less aggressive and equally effective ways to remove patina on highlights. The H&H media uses silicon carbide abrasive which removes detail as well as patina (read their description). Any of the mild abrasives such as Rio’s clean cut media will do a good job. Using a vibratory tumbler with a mild abrasive is the best choice. The H&H media is so aggressive because it is used in a rubber rotary drum (and you need an extra drum to use it if you ever want to run steel). Drum rotary tumblers are best reserved for burnishing with steel media. I find that 10 to 15 minutes in a vibratory tumbler with blue fine clean cut media cones takes off just enough patina. The shape of the media dictates how far it digs into crevices and stampings. Incidentally, I use the fine cone media as a final finish for all satin finishes.
I also recommend Hone and Highlight. I use this now combined with SS shot after or just a polishing cloth to gloss the “highlights” a bit. If you don’t mind a more matte finish on your pieces and are looking to really create contrast with LOS and have lots of texture, it’s really a good product.