COKEDALE — Jack Van Heesch experimented hard with all sorts of psychedelics back in the day. “It was a party,” said the full-bearded, 66-year-old resident of this former Colorado mining town perched in the shadows of the Spanish Peaks in Las Animas County. Van Heesch was one of nearly 1.3 million Coloradans last November to vote for Proposition 122, which decriminalized the growing, use and sharing of psilocybin and psilocin — key compounds found in “magic mushrooms” — along with ibogaine, mescaline and dimethyltryptamine, or DMT. But his was a rare yes vote in Cokedale, a tiny hamlet of 150 hardscrabble residents seven miles west of Trinidad.