How to identify and date a vintage mahjong set
An old set in a leather case can be a family treasure or a bargain find. Two quick checks tell you roughly when it was made and whether you can play with it: count the flowers and jokers, then look at what the tiles are made of.
By Jerry Chen. Checked and updated November 1, 2026
Step 1: count the flowers and jokers
The National Mah Jongg League changed how many flowers and jokers the game used for decades, and American set makers followed. That makes the count a useful dating clue for sets made for American play.
| Period | Typical count | Notes |
|---|---|---|
| 1920s | 8 flowers, no jokers | The standard set of the first American craze. |
| 1937 to 1942 | 8 flowers | The new League treats flowers as wild. |
| 1943 to 1960 | 12 to 24 flowers | Flowers added year by year, peaking at 24 in the early 1950s. |
| 1960 to 1971 | Jokers appear, 2 to 8; flowers drop to 6 to 14 | A set with 14 flowers and 2 jokers was probably made in the early 1960s. |
| 1971 onward | 8 flowers, 8 jokers | Today's standard. |
Summarized from Tom Sloper's year-by-year table of League flower and joker counts (column 509). Some 1940s American sets already had two jokers, and some Chinese sets of uncertain date include jokers, so treat the count as a clue, not proof.
Why so many odd sets survive: when the League called for more flowers, players topped up their sets with extra tiles and flower decals, so flowers often do not match the rest of the set.
Step 2: what are the tiles made of?
- Bone and bamboo
- A bone face joined to a bamboo back, found in many older Chinese-made sets. Tom Sloper notes some are later than they look, possibly as late as the 1960s.
- Bakelite (molded phenolic)
- Leo Baekeland's 1907 plastic, the first fully synthetic one. It was usually pressed from powder in a hot mold, so it tends to be dark: amber, brown or black. Very tough.
- Catalin (cast phenolic)
- The same family of plastic, but poured as a liquid into molds, which allowed bright, light and translucent colors, including the swirled "apple juice" look. Cast phenolics were made widely after Bakelite's patent ran out in 1927. They are weaker and can warp or crack with age, and white tiles yellow over time.
- Casein
- A milk-based plastic of the 1930s and 1940s. Tiles cut from casein sheet tend to be flat and matte with sharp corners, where molded phenolic tiles are glossy with rounded corners.
- Later plastics
- Many later sets are polystyrene (hard and ceramic-like) or polyethylene (soft and slightly waxy). The clear layers in modern layered tiles are often acrylic.
In everyday sales, "Bakelite" is used loosely for almost any vintage American phenolic set. A restorer Tom Sloper consulted said light-colored mahjong tiles are almost certainly Catalin, because Bakelite is rarely that light.
Home tests collectors use
None of these is conclusive, and all of them can harm paint, gilding or a lacquer finish. Test only on the back or side of a single tile.
- Hot water: hold the tile under hot tap water and smell it. Phenolics give off a formaldehyde smell; celluloid smells of vinegar or camphor.
- Polish: rub a little metal polish such as Simichrome on the back with a white cloth. Phenolics often turn the cloth yellow. Black or lacquered pieces may test negative anyway.
- Sound and weight: phenolic tiles clack together with a solid "clink" and feel heavy for their size.
Do not burn or scrape tiles to test them.
Step 3: will it play today?
Today's American game uses 152 tiles: 108 suit tiles, 16 winds, 12 dragons, 8 flowers and 8 jokers. Many vintage sets are short of jokers. The usual fix is joker stickers on spare flowers or blanks, sized to match your tiles. Check also that the racks are long enough to push a wall of 19 stacks. Check a set's tile counts or read how many tiles you need.
Caring for old tiles
- Wipe tiles with a barely damp cloth and dry them straight away. Do not soak painted or bone-and-bamboo tiles.
- Yellowing from age is a change in the plastic itself and cannot be cleaned off.
Buying a vintage set
Ask the seller for the exact count of flowers, jokers and blanks, photos of the backs and edges, and the rack length. What to check before buying a vintage or used set.
Common questions
How can I tell how old my mahjong set is?
Count the flowers and jokers. 8 flowers and no jokers points to the 1920s or 1930s; lots of flowers (12 to 24) and no jokers to the 1940s and 1950s; a few jokers with extra flowers to the 1960s. It is a clue, not proof: sets were often topped up later.
Is my mahjong set Bakelite?
Many vintage American sets are called Bakelite, but most light-colored tiles are probably cast phenolic, often sold as Catalin. Collectors use a hot-water smell test or a polish test on the back of a tile; neither is conclusive and both can damage painted surfaces.
What is the difference between Bakelite and Catalin?
Both are phenol-formaldehyde plastics. Bakelite was usually molded from powder under heat and pressure and tends to be dark. Catalin was cast from liquid resin, which allowed brighter, lighter and translucent colors.
Can I play American mahjong with a vintage set?
Usually, once it has enough jokers. Today's game needs 152 tiles including 8 flowers and 8 jokers. Older sets can be brought up to standard with joker stickers on spare tiles or blanks.
What is "Chinese Bakelite"?
A term used by sellers for some older Chinese-made plastic sets. Tom Sloper notes it is not a defined material and suspects many such tiles are polystyrene or casein rather than true Bakelite.
Are old bone mahjong sets ivory?
Most old Chinese export sets are bone and bamboo, not ivory. If you think a set might be ivory, check the laws where you live before buying or selling it: the United States banned ivory imports in 1989.
Sources: Tom Sloper, flowers and jokers by year (column 509); Tom Sloper, FAQ 7c3 on plastics; Tom Sloper, history timeline; Cool Old Games, Catalin vs Bakelite; MAFCA, Celluloid or Bakelite?