Carbonado compared to carbon‑12, relative to typical diamonds). Carbonado exhibits strong luminescence (photoluminescence and cathodoluminescence) induced by nitrogen and by vacancies existing in the crystal lattice. Luminescence halos are present around radioactive inclusions, and it is suggested that the radiation damage occurred after formation of the carbonados, an observation perhaps pertinent to the radiation hypothesis listed below. The origin of carbonado is controversial. Some proposed hypotheses are as follows: None of these hypotheses for carbonado formation had come into wide acceptance in the scientific literature by 2008. Supporters of an extraterrestrial origin of carbonados propose that their material source was a
Rock Eagle Rock Eagle Rock Eagle Effigy Mound is an archaeological site in Putnam County, Georgia, U.S. estimated to have been constructed c. 1000 BC to AD 1000 (1,000 to 3,000 years ago). The earthwork was built up of thousands of pieces of quartzite laid in the mounded shape of a large bird (102 ft long from head to tail, and 120 ft wide from wing tip to wing tip). Although it is most often referred to as an eagle, scholars do not know exactly what type of bird the original builders intended to portray. It is listed on the National Register