Comments posted to our Dark Souls 2 Wiki
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I wish that there were concrete rewards tied to what you dropped them. Got my fourth titanite Slab in a row now when I could really use a Petrified Dragon Bone or a titanite Chunk
Whether I use a petrified, large, or small stone I seem to have a 50% chance to get a demons great hammer. Halfway through the game and I have about 15 demon hammers.
Sell a few to Gavlan. More souls!
I got a human effigy from a small smooth and silky stone once
I got both the trident and the whip from a small and silky stone. Luck, I guess.

Disappointed with the durability on the Trident, however.
Well every weapon is made of wet cardboard
Just stack up on repair powder
lol i used 17 smooth and silky stones and 5 petrified somethings and still didnt get the white ring
Got white ring very first time I left a small smooth and silky stone
titanite Slabs are way too common. I'm nearly halfway through this game and already got five of them from these guys.
I've gotten a bunch of Amber Herbs and Lifegems from dropping Prism Stones, but they're not listed here.