Carbonado in the pores that are common in carbonados, they may have been introduced after carbonado formation. Inclusions of other minerals, rare or nearly absent in the Earth's crust, are found at least partly incorporated in diamond, not just in pores: among such other minerals are those with compositions of Si, SiC, and Fe‑Ni. No distinctive high-pressure minerals, including the hexagonal carbon polymorph, lonsdaleite, have been found as inclusions in carbonados, although such inclusions might be expected if carbonados formed by meteorite impact. Isotope studies have yielded further clues to carbonado origin. The carbon isotope value is very low (little carbon‑13
What Is This? What Is This? What Is This (known prior to 1980 as Anthym) was a rock band that originated in Fairfax High School in California and would play numerous shows along the coast of California. It was formed by guitarist Hillel Slovak, drummer Jack Irons, vocalist Alain Johannes, and bassist Todd Strassman. Originally named Chain Reaction, the band would later change its name to Anthem, then later to Anthym (as there was already a band using the former moniker), and then finally to What Is This, which was a tongue-in-cheek reference to the reaction they usually received from first-time listeners. During