Aetna Blue, sometimes listed as Etna Blue, is a dusty, medium-toned blue with quiet depth. It appeared on several air-cooled 911 generations and has the kind of understated quality that Porsche's more contemplative buyers have always gravitated toward. It is not a color that announces itself, but it rewards close inspection. The name references the famous Sicilian volcano, and there is something appropriately elemental about it.