Certificate of Authenticity for the 100% Japanese Wagyu Beef served at Greystone by newsadmin | Mar 1, 2018 | NewsThis is a Certificate of Authenticity for the 100% Japanese Wagyu Beef served at Greystone, which has the HIGHEST QUALITY grade in Japan! Come in and try this delicious dish. www.greystonesteakhouse.com/wagyu-beef/