A superhard carbon composition, having a crystal structure cell consisting of (i) a unit cell of six carbon atoms with crystallographic hexagonal symmetry, (ii) all carbon atoms in flat three-fold coordinated configurations (sp.sup.2 bonding), and (iii) carbon atoms in layers of chains which zig-zag...http://www.google.se/patents/US5110577?utm_source=gb-gplus-sharePatent US5110577 - Process of depositing a carbon film having metallic properties
