Q. I put my living stones in full sun on my new porch, and after a day they all when ghost white. Are they dead?
You moved living stones (Lithops) into direct sun and are experiencing some bleaching, turning them gray white. They may be ok. I would move them into partial sun and gradually move them into total sun over a few weeks. Plants growing under lamps need to be acclimatized to the outside gradually over a few weeks.