The three cakes in the image above are made from the same raw tea leaves. One is machine-pressed, one is stone-milled, and another is semi-machine semi-milled. Can you tell which is which?
The pressure from stone milling is limited to the weight of the person and the stone mold, making it the lightest. Machine pressure is adjustable but generally less flexible than a stone mold, so it is usually heavier.
The semi-machine semi-milled cake is my favorite. It is first pressed with a machine (using less pressure than pure machine pressing) and then shaped with a stone mold, resulting in pressure between that of stone milling and machine pressing.
The top right cake is clearly under the greatest pressure, with the tea strips flattened—this is machine-pressed. The top left cake is the loosest, indicating stone milling. The bottom cake is semi-machine semi-milled, exhibiting characteristics between the two.
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