Why is my cat twitching in their sleep? Vet's guide to dreaming vs. seizures

✨The Polished Cat’s Eye Stone Bracelet — where natural light dances through every hand‑polished bead. Crafted from genuine cat’s eye stones, it carries a quiet energy that calms and captivates. A piece born of earth and touch — more than jewelry, it’s your inner light made visible.✨ https://jangoodsmart.com/products/captivate-every-gaze-the-polished-cats-eye-stone-bracelet | Jan Goods

Is cats eye a natural or manmade/synthetic stone? If it’s natural, does this one look real? (likely dyed; does not scratch with metal nail file, was $5)