I was going through my vaults making some space and found some of these that I bought at the Hollow Eve fest 2-3 years ago when I got it in my head that I was going to be unique and be Sling primary(SPOILER ALERT: Slings: 48 90.76% it lasted until about Goblins).

http://elanthipedia.org/w/index.php/Weapon:Pyrite_clump


If anyone wants some, just email my play.net address and be in the Crossing and they're yours for free. I don't know how they compare to other readily available sling ammo, but I have 360 of them(I... I like to have extras) and in a couple of days they'll just get fed to the gelapod or tossed in a bucket.