What should I alch?

I'm currently going to do about 100k alches on my Pure. And I need to know what to alch to loose Minimal amount of Gp. Also don't give me alchprices.com, or anything like that. I want an item That I can buy great quantities of.

 

Here's an alchemy calc: http://www.scape-xp.com/runescape-high-alchemy.html

Just pick a couple of those items and buy it to alch.

Good ones which you can buy decent amounts of seem to be onyx bolts (e), rings of forging, and phoenix pouches.