A name like Special Finest Tippy Golden Flowery Orange Pekoe reads like a citation, but nobody sits and composes it. It is assigned by machine, by dried leaf falling through a stack of sieves fitted with mesh sized 8, 10, 12, 16, 24, and 30 or finer, each screen holding back one size and passing the rest down to the next (KKHSOU Tea World, the state open university's own account of the process). This office has already certified the shape of that principle: leaf is made, then sorted on oscillating sieves of decreasing size. What that certificate does not name is the machines that do it, the mesh numbers stamped on their screens, or the plain fact that after all of them, the best grades still pass through a human hand.

The first machine pulls the stalk out, nothing else

Orthodox leaf meets the sieves through a machine called, without embellishment, the Myddleton. It is built to do one job: separate stalk and fibre from the made leaf before any size grading starts, and by trade accounts it is the only machine on the floor that can (GK Tea). Aluminium sieves, dimpled and perforated in two sizes, are set oscillating by a crankshaft turning at roughly 200 revolutions a minute, fed at a steady 1,500 to 2,000 kilograms an hour (about 3,300 to 4,400 pounds). Fine tea drops through; stalk, fibre, and lumps ride the surface and are pushed off the end. What spills over the top does not move on yet. It runs through a second machine, a rotary hexagonal sifter the trade calls a ghugi, for another pass before the leaf is fit to grade by size at all (KKHSOU Tea World).

Two more sorters, and a mesh number for every grade

Only now does the actual size sort begin, and it runs on the machines whose names show up on a spare-parts invoice, not a tea tin: the Arnott sorter and the Macintosh sorter. Leaf from the ghugi trays feeds into both. A machine built to the Arnot design runs five or six wire-mesh decks stacked one below the other, each deck strung with a different mesh, oscillating at around 480 revolutions a minute off a two-horsepower motor, and the tea sorts as it works down through the stack (teaengineering.in, a tea-machinery builder). Each deck's mesh size decides which grade drops there, the same 8-to-30-or-finer ladder KKHSOU records, so the letters on the packet, whole leaf down to the smallest broken grade, are really just names for which numbered screen a given piece of leaf fell through. CTC and leggcut tea, which has no whole leaf to protect, runs the same sizing logic through a Macintosh sorter and a third machine built for it, the Britannia Tea Sorter.

What one grade actually passed through

Take a bag of BOP, Broken Orange Pekoe, off a shelf and the letters name a physical route, not a description somebody wrote. That leaf went through the Myddleton first, lost its stalk and fibre there, made a second pass through the ghugi, then dropped into an Arnott or Macintosh tray sized for the broken grade specifically, one screen among the 8-to-30-or-finer ladder, and passed through a wind tunnel afterward to lose whatever fibre and dust rode along at the same size. A finer grade, a Pekoe Fannings or a Dust, is the same route continued one or two screens further down, where the openings are smaller and the tea that drops through is smaller too. The letters on the packet are a record of which screen stopped the leaf, nothing more mysterious than that.

Air does the job a mesh cannot

A screen only sorts by size, and fibre and true tea can share a size while weighing differently, so the mesh alone would let stray fibre and dust through into a clean lot. The floor's answer is air, not a finer screen: wind tunnels and waterfalls drop the sorted tea through a moving column of air, and fibre and dust, being lighter for their size than whole tea, are carried off while the denser leaf falls straight through (KKHSOU Tea World). UPASI Tea Research Foundation describes the same principle at work on the CTC line by a different specific method: electrically charged PVC rollers pull fibre and flaky tea off the sorted granules by the same difference in moisture and density, not size. Two separate machines, the same underlying trick: let gravity and weight do what a mesh cannot.

What the mesh still cannot finish

Here the machinery reaches its limit, and the record says so plainly: "a number of hand sievings are also essential to produce some quality grades" (KKHSOU Tea World). A vibrating screen sorts by size alone; it cannot see that one piece of leaf carries more golden tip than its neighbour of the same size, or judge a borderline lot the way the top grades demand. For those, a sieve is still worked by hand, a tray shaken and turned by a person standing over it, doing by touch and eye what no screen on the floor is built to do. The ornate names at the very top of the alphabet, Finest Tippy Golden Flowery Orange Pekoe and the Special grade above it, are not just machine output. They are machine output finished by a hand sieve, because the mesh stack cannot tell a fine pick from a merely correct-sized one.

Whose hand it usually is

That hand belongs, more often than not, to a man. Fieldwork behind Oxfam's 2019 report on Assam's tea plantations, based on interviews across fifty estates, found that "work in the factories, which is better paid, has better facilities and is regarded as more dignified and prestigious, is done predominantly by men," while the plucking that fills the factory's intake is the work women are assigned. The people who grow and pick Assam's leaf are, by and large, the descendants of labour recruited from outside the valley from the 1860s on; the sorting floor sits downstream of that same workforce, and the two jobs, field and factory, are not held by the same hands or paid the same wage.

A tea's grade letters are a sorting record, not a taster's title. Most of the alphabet comes off a numbered screen. The finest of it comes off that screen and then a hand, at a sieve no machine on the floor has replaced. The packet does not say which is which. It only says the leaf passed.

Sources

1. Sorting and Grading of Tea, KKHSOU Tea World, Krishna Kanta Handiqui State Open University (the mesh sizes, the Myddleton, ghugi, Arnott, Macintosh and Britannia machines, the wind-tunnel and waterfall separation, and the hand-sieving line).
2. Orthodox tea manufacture and grades, UPASI Tea Research Foundation (the oscillating-sieve principle and the orthodox grade list).
3. CTC tea manufacture and grades, UPASI Tea Research Foundation (density-based fibre separation and the CTC grade list).
4. Tea Arnot Machine, Tea Engineering (the Arnot-design multideck sorter: deck count, mesh-per-deck, and running speed).
5. Myddleton Stalk Extractor, GK Tea (the machine's sieve sizes, feed rate, and role as the first stage of orthodox sorting).
6. Addressing the Human Cost of Assam Tea, Oxfam International (2019), full report, p. 25 (the gendered split between factory and field labour, based on interviews across 50 Assam tea estates).