These came out beautifully in my shower renovation. After calling the manufacturer Pebble Tile, we were told they were made of MARBLE. I tested two separate sealant products, one which simply sealed the stone and one which is a color enhancer  (DuPont Stone Tech Enhancer Pro) and the difference is amazing! I liked them dusty grey but the Enhancer really made them amazing! You can judge for yourself based on the photos but either way these were perfect! I purchased them on sale for ~$6/sqft... the manufacturer sells them by the soft around $7 so I wouldn't pay wayfair full price. (Pictures are before grouting)