1 on a corpse in the Iron Keep after turning off the fire in the room near the Smelter Demon.
1 in the Shaded Woods, in a wood chest one level above the "Shaded Ruins" bonfire (can be respawned by burning a Bonfire Ascetic).
1 on a corpse in Brightstone Cove Tseldora, out the door and right from the "Lower Brightstone Cove" bonfire.
1 from the blue crystal lizard in Brightstone Cove Tseldora near the "Chapel Threshold" bonfire.
1 in the Doors of Pharros, inside a trapped chest near the spike walls.
1 in a chest in one of the side rooms with the two Warrior Giants below Black Gulch.
3 in Dragon's Sanctum in the hallway with the repeating arrow trap after hitting the switch on the ceiling.
1 in the Shrine of Amana, after the third bonfire lying in the water.
1 in the Undead Crypt, in the first room past the second bonfire on the ground.
1 on the ground, in a bush just after and left of the gate before Aldia's Keep, near the first bonfire. Right where you get attacked by the rat-dog things who try to petrify you.
1 after the skeleton dragon in Aldia's Keep in the mirror gallery behind the stairway.
1 in the pool of corrosive acid past the second bonfire Aldia's Keep. (Farm this one as you farm Dragon Scale and Soul Geyser).
8 can be found in an iron chest in Brume Tower behind a breakable wall in the room past the Foyer Bonfire by blowing up a barrel kobold near it.
2 can be found on a corpse in the tower where you retrieve the red iron scepter.
2 can be found on corpses in the Dragon Aerie. The treasure is behind the dragon eggs on the path to the right before the second wyvern (it is also worth noting that it is possible to farm the crystal lizards in the area for the bones as they frequently drop them, however, this requires the use of bonfire ascetics).
3 can be purchased from Stone trader Chloanne for 17500 each (after obtaining the King's Ring).
Possible trade for Petrified Something, Smooth & Silky Stone, or Small Smooth & Silky Stone from Dyna and Tillo at Things Betwixt;
One on the body before Looking Glass Knight boss, passage way through stoned Llewellyn knights
Drops from
1 drops from Ancient Dragon in Dragon Shrine.
1 drops from the Great Basilisk in Shaded Woods, near "Shaded Ruins" bonfire.
Randomly drops from the Great Basilisk in Aldia's Keep.
Randomly drops from Dragon Acolytes in Aldia's Keep.
Randomly drops from the Wyverns in Dragon Aerie.
Randomly drops from The Imperfect near the third bonfire of Dragon's Sanctum. Relatively high drop rate with drop chance increasing items equipped.
Randomly drops from the Frozen Reindeer monsters in Frigid Outskirts.
