Pressed square oolong
The only compressed oolong there is. A finished oolong manufacture, interrupted before drying so that the damp leaf can be pressed into a small paper-wrapped square and baked inside its wrapper.
What makes this route what it is
A press placed before the drying rather than after it, which no other route in the catalogue does. Every dark tea in the catalogue dries its leaf and then steams it damp again to press it; this one never lets the leaf dry in the first place, and the whole format follows from that one piece of ordering.
The route, in order
Each note describes what the step is doing in this route. The same operation does a different job in a different chain.
A conventional short sun wither. Everything through step four could be any Fujian oolong.
Shaking cycles, taken to a light-to-moderate oxidation. The style is not a heavily oxidised one, which matters because the long bake to come would otherwise take it much further than intended.
Ordinary fixation, judged as in any oolong.
A rolling pass that leaves the leaf pliable and damp. In every other oolong route the next thing that happens is drying, and here it deliberately is not.
Pressed damp into small paper-lined wooden moulds, a few grams to a square. The leaf's own moisture is what lets it take and hold the shape, which is why the press cannot be moved later in the route.
The paper is folded closed around the square before baking rather than after it, so the wrapper is part of the manufacture and not packaging. It is the reason the finished squares hold their edges.
A long, low bake with the paper on, in several passes. Slow because heat has to reach the centre of a pressed block through a wrapper, and this is where a batch is lost if it is hurried.
How it differs from its neighbours
A route described on its own teaches very little. The useful fact is always which other route it is nearly identical to, and where it leaves it.
Both routes use the same operations. Only their positions differ, and that is the whole of the difference between the two teas.
Both routes press leaf into a shape and dry it. The white cake dries the loose tea first and then steams it damp again in order to press; this one presses leaf that was never allowed to dry. Same three operations, opposite arrangement, and the reason one cake is a storage format and the other is the tea itself.
This route inserts an operation the other does not have. Nothing is substituted and nothing is removed.
An oolong route with a press inserted into it. Nothing else is substituted — the wither, the shaking, the fixation and the rolling are the neighbouring manufacture — and one operation produces a format that no other oolong in the world has.
Where it goes wrong
A square pressed too hard or baked too fast dries at the surface and stays damp in the centre, which is the classic setup for the tea going off inside its own wrapper — a fault invisible until it is opened. Under-pressing gives a block that falls apart in the packet and loses the slow opening the format exists for.
In full
Compression belongs to the dark teas and, latterly, to white tea. One oolong production uses it, and the shape of the route explains why it stayed unique. After an ordinary oolong front end — sun wither, shaking, standing rest, fixation, rolling — the leaf is not dried. It is packed while still pliable into small wooden moulds lined with paper, pressed into squares of a few grams each, folded closed in the paper, and only then baked, slowly, in the wrapper it will be sold in. The paper stays on until the drinker takes it off. That order is what makes the tea: pressing dry oolong would shatter it, and drying first and pressing after — the order every dark tea uses — is not available, because there is no steaming step here to soften anything back up. The result behaves in the pot like neither a loose oolong nor a dark tea cake, opening slowly from a block that was never allowed to become brittle.