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
Flake tool the blow from the strike it distributed onto the rock in an even fashion, giving the fracture a radial appearance. The production of these lithic tools is only made possible due to their ability to fracture in this way. Examples of such materials include fine-grained materials, such as carbonado, volcanic rocks, obsidian, onyx, and types of glass. These would all be excellent materials for creating flake tools. Flake tools can teach us much about human history. Residue analysis can be done to learn what was processed by the flake tools. Use-wear analysis can give archaeologists an idea of what the