Trans-Petrification

A Ritual spell casted on a gemstone necklace. Upon casting of this spell the caster can wear it without harm but once someone else wears the necklace they will begin to slowly transform and turn to stone. The transformation can vary from the race of the cursed wearer to even a different thing in general. The transformation and petrification takes roughly 8 hours and typically wont be noticeable till the 3rd or 5th hour. It starts where the necklace is and even after petrification the wearer remains consciousness. Some believe that some gargoyles are actually people who fell victim to this spell. The stone that was used in the Ritual will also bind itself into the newly transformed statue and if magic is casted upon the gemstone it will allow anyone with magic to take control of the statue effectively turning it into a stone golem.

The petrification can be undone by the caster or by standard means that remove the petrified condition. The transformation part is otherwise permanent unless the uss of shapechange or true polymorph (changeling is an exception tho any additional appendages added due to the transformation will stay no matter what the changeling changes into)