Metropolitan Tea has travelled the world to bring you the best in luxury quality tea at a fair price. DISCOVERY HERBAL : GREEN YERBA MATE. Greenish and vegetative. Mate is rich in caffeine and was used as a caffeine beverage in Latin America before the advent of coffee. Luxury Ingredients: Green Mate. Small Batch Blended and Packed in: Canada. Tea(s) From: Brazil. Region(s): Parana. Antioxidant Level: Very High. Caffeine Content: Medium.