All those letters after the tea - what do they mean? Good question. Here are some answers.
As you know other agricultural products use grading systems to determine the worth of the crops or produce in relation to each other. Eggs use size (small, medium etc.) wines also have a system that is meant to communicate who grew the grapes, what grapes where used.
For tea, letters indicate the grades, size of the leaf, and which part of the leaf it is. Remember that fine teas are picked from the first two leaves and a bud. That doesn't mean the larger leaves are not picked.
BOP means Broken Orange Pekoe. These pieces are considerably larger than Fannings and are often very fine tea based on where they come from.
OP stands for Orange Pekoe and generally indicates that its the second and larger of the "two leaves and a bud". Nonetheless, these are whole leaves and may be excellent teas.
FOP is stands for Flowery Orange Pekoe and is the indication that the first two leaves and the bud are present. At this point you have very good whole leaf tea.
The other letters refer to the more esoteric characteristics of the tea (understood by a chosen few).
G stands for Golden - Usually put before BOP (GBOP) to indicate that there are pieces of the bud in amongst the rest of the leaves. Those pieces are yellow and visible.
T stands for Tippy and that the whole leaf bud is present in a substantial quantity. You will see it as TGFOP. (Tippy Golden Flower Orange Pekoe)
FTGFOP is Finest Tippy Golden Flowery Orange Pekoe.
SFTGFOP stands for Special Finest Tippy Golden Flowery Orange Pekoe.
CTC applies to tea leaves which have been cut, torn and curled.
BPS refers to Broken Pekoe Souchong
FNGS is for Fannings or the next size up from Dust. Dust and Fannings are used in tea bags because they are small enough.
D is for Dust or very small particles of tea left over after processing. This is the lowest grade of tea as tea is graded on size of leaf not necessarily quality
These grades only apply to Black Teas.