So with the February Monthly Achievement; we need to salvage 500 items. This comes out to roughly 18 per day (assuming you play every day this month); but for the sake of argument lets say I want to salvage 25 items per day.
What areas have mobs that will drop salvageable items at an acceptable rate?
Ideally; I'd think you'd want enemies that would typically drop armor/weapons. Ones that drop rare crafting materials (while helpful) seems to be less important. Also; it seems like you'd want to avoid enemies that drop bags (as you get no salvage points for them).
My assumption is that I'd want to run dungeons a bunch of times (3 fractals seem to fill up a good chunk of my inventory) as well as areas with lots of humanoid enemies (pirate/bandit camps)
Another viable strategy seems to be spinning up a new alt and ranking up my crafting skill and then salvaging the created items. (Currently my main is an ele with Tailor/Artificer; so fire up a ranger with Leatherworking/Huntsman)
Best Answer
Right now there are Malachite Copper Rings available for 31 copper each (58k of them). These are just the first item I found and may not be the cheapest possibility.
If you bought 500 of these, it would cost 1g55s. If you salvaged them (using cheap honor kits) and only got 500 copper ore, you would recoup 70s at immediate sale prices. That would net out to 85s cost.