According to Official Guinness Records,
The largest collection of 3-piece tea sets consists of 999 full sets and belongs to Pyrmonter Fuerstentreff (Germany), displayed in Bad Pyrmont, Germany, on 7 July 2012.
The record attempt took place during the 16th annual Pyrmonter Fuerstentreff, a three day historical festival, and the tea sets were displayed on a 300 m (984 ft and 3.02 in) table. The 999 full sets consist of 2,097 individual pieces of porcelain. Each set was unique.
For a complete list of 2012 records, please visit 2012 Guinness Records in Germany.