I just bought them, but didn't think to ask the salesman what they were. Gemstone changes from brown (artificial light) to pink (natural light). The larger necklace was $250 : r/whatsthisrock
EGL Certified 14.45 Ct Natural Cushion Zultanite Color Changing Turkish Best Gem | eBay
What is zultanite? What is zultanite worth? A definitive guide