An engraver I first learned some basics from 50yrs ago used a lube on the graver points of those that he used to work gold and silver inlays.
His primary work many year before this was in the jewelry engraving trade and this was a hold over from that.
These were the hand gravers only that he used it on (hand pushed),,not the chasing tools when cutting steel.
He used to lube the point of the gravers when detailing the gold and silver inlays on the firearms.
He used Wintergreen Oil for the lube.
A mere drop or two in a cotton ball,,that pushed into a bottle cap setting on his bench close at hand. He'd often just quickly touch the point of the graver to the cotton and continue work.
It was to prevent the sometimes sticky feeling of the steel graver in the soft gold and silver, especially 24k gold.
Worked well for cutting brass, copper, aluminum too. Any of the non-steel metals that might be put in front of you.
He said it was common in the trade (Jewelry Engraving) and he just had that habit of doing the work on the precious metals that way.
He was a firm believer in a high polish on the points, and for steel cutting that sufficed in getting a nice clean cut with the proper sharpening angles. No graver lube necessary there.
I used a graver lube as he did for a time,,following his lead naturally. But dropped the effort after a while as I would just plain forget to go back and relube the point.
Plus my style of detailing gold/silver inlays developed into a different method than his and didn't require as much or any removal of the metal.
So the lube is still buried somewhere under the piles of stuff on the bench somewhere I think along with the Chinese White.
Antique almost! Maybe they have some Ebay value..!