What a relief to find out the cap and gown I am wearing for my MLIS convocation is made of 100% post consumer recycled plastic bottles.
"For every San Jose State University graduate walking at commencement, an average of 23 plastic bottles were used to manufacture the Cap and Gown, keeping the bottles out of our landfills. The new line of graduation wear is called GreenWeaver® . It is the latest effort to go green on campus by converting discarded water bottles into keepsakes."(http://www.oakhalli.com/college/sanjosestateuniversity/)