From an article at Colossal:
"Washington-based artist and researcher Heidi Gustafson forages, processes, and catalogs natural mineral samples for the Early Futures Ocher Archive. Ranging in color based on its elemental structure, ochre is crushed into a powder and used in various applications from art to medicine. With over 550 samples, Gustafson’s ever-growing archive has become a collaborative project with contributions from archaeologists, scientists, and creatives from around the world."
"As each sample enters the collection, it is labeled with a corresponding number. In a notebook, Gustafson records where the ochre is from, who sourced or collected it, any historic or contemporary uses, and other relevant information. Gustafson grinds the iron-rich ochre into pigments, which she sells to artists and also uses for her own work. Processed samples are added to glass vials and organized by region or dominate mineral type."
It's easy to see why such minerals were so valuable to early humans. There are additional interesting photos at the artist's Instagram site.
Addendum: This is a photo of the shoreline at Hormuz Island -
- where there are immense deposits of ochre. Look at this gif of the shoreline.