Haven't been posting around here much, but I think I'll kick things off with a bang. /ohmy.gif" style="vertical-align:middle" emoid=":o" border="0" alt="ohmy.gif" />
I can't work out what you are killing though and how long were you there to get that amount of charms?
Armored Zombies down at the Defender of Varrock tunnels (trapdoor at the Chaos Temple in the Wilderness). Best experience I've seen yet, with 100K experience an hour is you're AFK'ing, and easily over 125K experience an hour if you're using Piety with the alter just up the trapdoor with full concentration.
And yes, it's quite a decent source of blue charms, based on my knowledge.