Qizi Cakes and 357 Grams: Where the Weight of a Tea Cake Comes From
Pick up a traditional round pu'er cake in a tea shop and the wrapper will often say "Net weight 357 g." It's an untidy number, yet it has been in use for more than half a century, and newly pressed tea still follows it. It's actually the result of two histories stacked on top of each other: the old Qing dynasty rule of "seven cakes to a tong," and a weight worked out from 20th-century export packaging.
The Qing Rule: Seven Rounds to a Tong
The tradition of "seven cakes to a tong" (a bamboo-wrapped stack) goes back to the Qing dynasty. After Pu'er Prefecture was established in 1729 (the seventh year of the Yongzheng reign), the imperial court began regulating the trade and taxation of Yunnan tea. According to the Da Qing Huidian Shili (Collected Statutes of the Great Qing, with Precedents), a rule issued in the thirteenth year of Yongzheng (1735) set Yunnan tea at "seven rounds to a tong, weighing 49 liang," and tea permits were issued and tea taxes collected by the tong.
Under that rule, one round cake weighed about 7 liang. Converting the Qing liang to today's metric units is not simple, and different sources calculate it differently. What we can say for certain is that a Qing dynasty cake and today's 357 grams are not the same number. The form of seven cakes per tong was passed down from the Qing; the 357-gram weight was set later.
In the late Qing and early Republican years, tea shapes became quite varied for a time; for example, there was a "xiao wuzi yuancha," a size smaller than the standard round cake. In the early Republic, tea merchants' associations in various places also tried to standardize cake weights again. For more on tribute pu'er and Qing tea administration, read Imperial Tribute Pu'er.
How 357 Grams Was Calculated
The most common and most convincing explanation has to do with export packaging after 1959:
- From 1959, China standardized on the market system of 1 jin = 500 grams.
- Pu'er for export at the time was shipped and traded by the "jian" (case), about 30 kilograms per case.
- One case held 12 tong, with 7 cakes per tong, for a total of 84 cakes.
- 30,000 g ÷ 84 cakes ≈ 357.14 g, which rounds to 357 g.
Looked at another way, it's also tidy: 7 cakes per tong × 357 g ≈ 2,500 g, or 2.5 kilograms, which is exactly 5 jin. When the Yunnan Provincial Gazetteer mentions Qizi cakes, it likewise describes them as "seven cakes together weighing about 2.5 kilograms." So the odd number 357 was divided back out from the round numbers of the case and the tong.
How cases and tong are packed (bamboo-sheath tong wrapping, 12 tong to a case) is illustrated in How to Read Pu'er Tea Packaging.
Why "Qizi Bing"?
In the 1950s, pu'er production shifted to state-owned tea factories, and round cakes were sold as "Zhongcha brand yuancha" (round tea); these are what collectors call the Yin-grade (Yinji) teas. In the early 1970s, Yunnan's tea import-export company, to promote exports, renamed "yuancha" (round tea) as "bingcha" (cake tea) and used the name "Qizi Bing Cha" (seven-sons cake tea) in place of the earlier Zhongcha brand round tea.
There are two accounts of the year of the change: one says 1970 (Chinese Wikipedia, citing the book Classic Pu'er), the other says around 1972–1973. The safest way to put it is "the early 1970s."
As for why "qizi" (seven sons) was chosen, besides continuing the old spec of seven cakes per tong, the common explanation in the tea world is that seven is a lucky number in Chinese custom, and "seven sons" also suggests many children, good fortune, and family togetherness, which makes it a fitting name for a gift. This is a popular explanation; no formal naming document has survived.
The Qizi cake era is also when four-digit recipe codes appeared, such as 7542, 7572, and 8582. For that story, read Hao-Grade, Yin-Grade, and Qizi Cakes: Three Eras of Vintage Pu'er and 7542, 8582, 7572: The Stories Behind Pu'er's Classic Recipe Codes.
Qizi Cake Does Not Mean Aged Tea
"Qizi cake" is a format and a name, not a vintage. It has been used from the 1970s right up to today, and newly pressed 357-gram round cakes are often called Qizi cakes too. When you see "Qizi Bing" on a wrapper, you still need to check the production date or batch number for the year; you can't judge age by the name alone.
What Other Weights Exist Today?
357 grams is the most traditional format, but pu'er today comes in far more than one size:
| Shape | Common weights | Notes |
|---|---|---|
| Round cake | 100 g, 200 g, 357 g, 400 g, 500 g | Small cakes are handy as gifts or for trying a tea; there are also big cakes of 1 kg or more |
| Tuocha | 100 g, 250 g, etc. | Bowl-shaped; Xiaguan tuocha is the classic example |
| Brick | 250 g, 1 kg, etc. | Square and easy to stack |
| Dragon pearls, mini tuo | 5–10 g each | One piece per session, no prying needed |
| Tea bags | About 2–3 g per bag | Broken leaf in bags; the most convenient |
The characteristics of each shape are covered in Cakes, Bricks, Tuo, Dragon Pearls, and Loose Leaf. Guyuntang's Bingdao Old Village Dragon Pearls are 8 grams each, exactly one session per pearl, a modern format where you "don't need to pry the tea."
What 357 Grams Means Today
Exports haven't been shipped in 30-kilogram cases for a long time, so why has 357 grams stuck around? Partly it's habit in collecting and trading: when the same tea uses the same weight year after year, it's easy to compare prices and to count by the tong and the case. Partly it has simply become the "standard look" of pu'er: when tea drinkers see a 357-gram round cake, they know it's a traditional-format pu'er.
FAQ
Why is a cake 357 grams and not 350? 357 grams was worked backward from export packaging: one case of about 30 kilograms held 12 tong of 7 cakes each, 84 cakes in all, and 30,000 grams divided by 84 is about 357 grams. It wasn't a deliberately chosen round number.
Where does the name "Qizi Bing" come from? In the early 1970s, Yunnan's tea import-export company renamed "yuancha" (round tea) as "Qizi Bing Cha" for export; accounts of the year differ between 1970 and 1972–1973. "Qizi" carries on the old spec of seven cakes per tong and also has connotations of luck and family togetherness.
What was the Qing rule of seven rounds per tong? According to the Da Qing Huidian Shili, a rule from the thirteenth year of Yongzheng (1735) set Yunnan tea at seven round cakes per tong, each tong weighing 49 liang, with permits and taxes assessed by the tong. Each cake was about 7 liang, which is not the same as today's 357 grams.
Are there other weights now? Yes. Round cakes commonly come in 100, 200, 400, and 500 grams; tuocha is commonly 100 grams; a dragon pearl is about 5–10 grams; and a tea bag holds about 2–3 grams.