The trap to know
The trap with dark tea is the oldest one in the category: fake age. It is also the most expensive mistake available in tea.
Aged pu-erh is sold by year, and the year is the single biggest driver of price. A 1990s cake and a 2015 cake differ by a factor of 10 or more.
There is far more old pu-erh on the market than was ever made, and the gap is filled with fakes.
The second version is wet storage, where a young cake is kept hot and humid to darken it and then sold as aged.
Both produce a tea that is worse than an honest young cake, sold at a large premium.
Everything below is about the checks that catch them.
A third version is simpler: a cake pressed recently with an old date printed on the wrapper.
Wrappers, neifi notes and storage stickers are all reproduced, and none of them count as evidence on their own.
Check the grade claim
For dark tea, grade names are less useful than production details, so check those instead.
For ripe pu-erh the useful facts are the factory, the recipe number and the year of pressing. A cake with none of those is unproven.
For raw pu-erh the region matters most. Lao Ban Zhang, Bingdao and Yiwu command very different prices, and all three names are used loosely.
A cake sold as a famous single mountain at a low price is almost certainly a blend, and possibly not from that region at all.
Leaf grade matters too. A cake made mostly from broken leaf and dust brews muddy, and it will never age well.
Ask whether it is a blend or single origin. An honest blend at a fair price is a better buy than a single mountain claim that is not true.
Ask whether the cake is sheng or shou, and be suspicious if the seller is vague. They taste different and they age differently.
Ripe pu-erh was only developed in the 1970s, so any ripe cake dated before that is impossible, and it still happens.
Smell before you pay
Smell is the most useful test for dark tea, because bad storage announces itself immediately.
A well stored cake smells of earth, wood, old books or camphor. All of those are normal and none of them are faults.
A musty, damp or cellar smell means wet storage. That is not character, it is spoilage, and it does not improve.
A sour or acidic note means the same thing, and it is the most common fault in faked aged cakes.
Smell the rinse water rather than the dry leaf if you can. It carries whatever is on the surface far more clearly.
If it smells of nothing, it is probably young tea stored dry, and it should be priced as young tea.
Taste settles what smell suggests. A clean cake is sweet and thick, and a wet stored one is thin, sour and leaves a dry finish.
If the liquor is very dark and cloudy on the first steep, that is a warning rather than a sign of strength.
Trust storage over label
Storage history is worth more than any date printed on a wrapper. Wrappers get reprinted.
The traditional split is dry storage, around 60 percent humidity at 25 degrees, against humid storage in Guangdong or Hong Kong.
Both are legitimate and they produce genuinely different tea. Neither of them should smell bad.
The problem is a cake that moved between the two, or was pushed hard to fake age, which is where the sour notes come from.
Buy from a seller who has held the cake themselves and can tell you where it sat. That is the whole test.
And if you are new to the category, buy a clean young cake from a known factory. It is the one part of this market where price and quality still track each other.
Buy a sample before a whole cake. 25 grams costs a fraction of a cake and tells you everything you need.
Keep your own notes on what you bought and from whom. In this category the seller’s history is the only thing you can really verify.