The art of grading tea leaves is one of the most complex aspects of the tea world. In fact, despite tea production being a huge industry and a global trade, there is no standard grading convention.
One grading convention, the one that we use and which is the most common for Indian and other East Asian black teas, is the Pekoe grading system. This system is based on the size of whole leaves, and whether or not they include the young leaf bud. A Pekoe is a tea that consists only of the flush of the tea plant - i.e. the young bud and the two topmost young leaves. Additional descriptors are added depending on the state of the Pekoe.
Whole Leaf Tea Grades:
Orange Pekoe (OP) - the standard Pekoe grade. The 'Orange' comes from the House of Orange, the Dutch royal family. When the Dutch East India Trading Company first brought tea to Europe, the best tea was reserved for the royal family, and eventually tea traders adopted the word 'orange' so as to associate their teas with royalty.
Flowery Orange Pekoe (FOP) - generally describes teas that only include the bud and the topmost young leaf.
Golden Flowery Orange Pekoe (GFOP) - teas with a higher proportion of tips, which are generally golden in colour.
Tippy Golden Flowery Orange Pekoe (TGFOP) - teas with an even higher proportion of tips.
Other descriptors can also be added to TGFOP teas, such as 'Fine' (FTGFOP) or 'Special' (SFTGFOP) as the proportion of tips goes up.
Broken Leaf Grades
When producing Pekoe tea, the leaves are passed through a series of sieves, separating the whole leaves from the broken leaves, and the broken leaves into different sizes. Broken leaf grades are generally catergorised by size into one of three tiers:
Broken - the highest grade of broken leaf teas, with the largest particles.
Fannings - particles that pass through the 'Broken' layer of the sieve are classified as 'Fannings'.
Dust - the smallest particles are known as Dusts or Sweepings.
All 3 of these categories are graded using the same descriptors as Orange Pekoe teas, for example Golden Flowery Broken Orange Pekoe (GFBOP), Golden Orange Fannings (GOF) and Broken Orange Pekoe Dust (BOPD). Fannings and Dust grades are the leafs that are most often used in commercial teabags.