Solitary Stone

 is a rare base item.

Obtained from
The item is available from the following vendors during the St. Patrick's Day event:
 * Pot O' Gold (Vendor) in the Watchtower
 * Pot O' Gold (Vendor) in the Hall of Doom

Feats

 * Knot Again: Collect 10 Base Items from the 2019 St. Patrick's Day event (10 Points)

Trivia

 * The item is only available during the St. Patrick's Day event.