it looks like stainless steel pennyround. I think Ann Sacks has a variety, as do other tile companies.
The textured wall in this image is a wall tile by Walker Zanger.
Bisazza tile diamond pattern silver and white backsplash
Susan Jablon Mosaics 1/4" Stix Subway tile.. http://www.susanjablon.com/catalogsearch/result/index/?p=1&q=stix
Bianco Asiago, a white marble used extensively in the Veneto region of Italy, where Prevedello’s family comes from.
etched glass with mirrored backing by Bendheim.