The use of mirrors in Mesoamerican culture was associated with the idea that they served as portals to a realm that could be seen but not interacted with. Mirrors in pre-Columbian Mesoamerica were fashioned from stone and served a number of uses, from the decorative to the divinatory.
More detailed methods of using the mirrors and others objects (media) for scrying are described in Wikipedia. One of the most famous scryers in history lived in the 16th century and was known as Nostradamus. He used a bowl of water or a “magic mirror” to “see” the future in it, while he was in trance.