These stones are created from the drying, freezing, and then BREAKing hearts skinned from Sun Vultures. There is a Mechanical Lore skill component to the process, that will likely be changed to the Alchemy skill.
It appears through a mechanical lore skillcheck the freezing step may be skipped. When using a wayerd pyramid to dry hearts; the pyramid will not message when it's done drying. You'll need to examine the heart periodically.
This material must be provided for alterations.
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