Black tea goes through five basic steps in which the process of oxidation is prolonged or in other words, it´s completely oxidized. The liquor obtained usually has tones that range from dark brown to copper red. It contains higher levels of caffeine than other teas while still constituting less than half the caffeine of one cup of coffee. Primarily produce in India, Kenya and Sri Lanka, black teas have stronger and more intense flavors and in some cases more astringency. The ideal brewing temperature is 212°F with a recommended infusion time of 3 to 4 minutes.