Abstract: A vascular or endoluminal stent is adapted to be implanted in a vessel, duct or tract of a human body to maintain an open lumen at the site of the implant. The sidewall of the open-ended tubular structure of the stent is a base layer of a metal biologically compatible with blood and tissue of the human body. An intermediate metal particle layer of substantially greater radiopacity overlies the base layer, with particles bonded to the base layer and to each other to leave interstices therebetween as a repository for retaining and dispensing drugs or other agents for time release therefrom after the stent is implanted, to assist the stent in maintaining the lumen open. The particles are composed primarily of a noble metal—an alloy of platinum-iridium. The sidewall has holes extending therethrough, and the particle layer resides along the outward facing and inward facing surfaces, and the edges of the through holes and open ends of the sidewall.