Well, I feel better after venting. Their marketers will tell you that the products make you live twice as long, protect you from cancer, and cure just about anything. They'll tell you that mineral deficiencies lead to a weakened immune system and cancer. You can buy the products as liquid supplements, aerosols, injectables, and vaginal douches. None of these claims have been proven.
Some colloidal minerals have long histories as medicinals.
In the 19th century, for example, colloidal silver was promoted as a treatment for everything from colds to rheumatism. Silver products are useful as germicidals, but over time, they've been replaced by safer and more effective ones. There is some potential for harm, as well. The body doesn't need silver, and it can accumulate in tissues, causing an irreversible bluish discoloration of the skin. There are even some reports of neurological problems in people who have used oral silver products long-term.