CandleSnuffer - I don't think any of the powder is coated today. Coatings would slow ignition, that's for sure, but rolling, milling and pressing time is what makes the gains of powder hard, sharp and shiny. The powder cakes are broken up, and seived. That which drops through the 4f seive is 4F, 3F, 2F, 1F and Cannon - it's all the same powder, today, I believe.
That's how I understand it, briefly. The harder the powder, the less breakdown and crumbling which causes dust. Dust which at least I took as being graphite, but learned it was not - right here on ALR.