Got a request about this. Not hard to guess the correct answer, but we need to find something definite we can point to. The request asks if there's anything to Moqui marbles widely sold on Nuage site. Nuage claims are that the stones are always either male or female and house spirits of Hopi ancestors.
"If they are indeed sacred to Native American tribes and linked to lore regarding ancestors, then they should most certainly not be dug out of the ground and sold the world over. If the story that they are part of the ancestral lore of tribes like the Hopi is new age woo, then its yet another form in which Native American spirituality is being exploited and that should be exposed."
What I find online so far is just a lot of stones for sale sites.