Magnesium diboride (MgB2) superconductor combines many unique features such as transparency of its grain boundaries to super-current flow. large coherence length. absence of weak links and small anisotropy. Doping is one of the mechanisms for enhancing these features. https://www.roneverhart.com/Corvette-Door-Handle-Accent-Leather-2005-2013-C6-Z06-ZR1-Grand-Sport/