Marco Antônio Guimarães is a Brazillian musician and instrument builder for the group Uakti.
Link to his facebook page- https://www.facebook.com/profile.php?id=100010422428675

An article in Portuguese on the instruments of Uakti- http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-75992011000100018

A guide to building an Uakti style glass marimba-
https://marimblog.wordpress.com/marimba-de-vidro/projeto-de-construcao/