D. M. Barringer, explorer of the eponymous Meteor Crater in central Arizona, spent a great deal of time and effort drilling for meteoric material. In his final paper to the Academy of Natural Sciences (March 1923), he stated that the samples from the last hundred feet were said to "show a very strong nickel test." Then, a "hard object" fell in against the side of the bit and wedged it solid. These drilling tools were abandoned and bypassed. Soon after this, the drilling was into material so hard only a few inches of progress could be made during a workshift. The drill tools were dulled and damaged by the material, the mystery of which may remain unanswered, for no cores were ever taken from this hole. The material brought up by the drill was "very black, very heavy with pieces of greenish metal showing." At 1,376 feet, the drill bit stuck for the last time in this material. Weeks of effort could not free it and on November 15, 1922 the hole was abandoned.* The only greenish metals are ruthenium and iridium, which are silvery but tinged with a greenish-yellow (ruthenium) or greenish (iridium) cast. Either or both of these elements could arrive as part of a meteor: the meteor credited with destroying the dinosaurs 65 million years ago left an iridium-rich layer of dust throughout the globe. Mysterious metals also abound in UFO literature, described in journals and newspapers from the 1890s onward. The most famous of these accounts is that of the 1947 crash at Roswell, where very thin, pieces of a lightweight, flexible metal were supposedly recovered. Not aluminum or tin; these are too familiar. Beryllium?