Zeolites are good for purifying water if the zeolites are left in the water for days. This is why zeolites are used in aquariums and is sold in aquarium stores as "Ammonia remover". So yes, water can be purified with the addition of minerals. Whether or not black mica, which is what this product is can do that is still to be seen.
I do find these statements made about the product to be interesting though:
"Adya Clarity is ‘Black Mica’. Zeolite AND Fulvic Acid are both derived from Black Mica. I feel that Adya Clarity is a much more superior product, does everything that these byproducts, Zeolite and Fulvic acid, accomplishes and MUCH MORE"
Free-standing, no electricity needed, gravity water filtration system. Includes a .2 micron ceramic filter, a multi-level filter of raw earth including activated carbon and zeolites, and a 16 ounce bottle of Adya Clarity (retail value of $125)
If Adya is so much more effective than zeolites as the first claim states then why would they even need a "multi-level filtration system including activated carbon and zeolites? If the Adya is as great at adsorbing toxins as they claim then I would think that other filtration media would not be required.
Also, not all zeolites are derived from black mica, as many forms, especially medicinal ones, exist independently.