Collectors often reach first for a famous material name. Begin instead with structure. Is the tile one material throughout? Does it have a separate face and back? Is there an obvious seam, mechanical join, pin, dovetail, or adhesive layer?
Bone and bamboo construction
Documented museum examples pair carved bone faces with bamboo backs. Look at the profile rather than relying on face color alone. Record how the two sections join, the relative thickness of each layer, and the tool marks. Visual signs may support a hypothesis, but photographs alone may not settle the material conclusively.
Early synthetic materials
“Celluloid,” “Bakelite,” and “Catalin” are frequently used as broad marketplace labels. Treat them as specific material claims, not synonyms for “old plastic.” The Smithsonian records a mahjong set with laminated celluloid tops and cellulose nitrate components, showing that early plastics are part of the historical record—but not proving that every cream-colored tile is celluloid.
What condition can tell you
Odor, stickiness, powder, crazing, warping, or discoloration can signal deterioration. The Canadian Conservation Institute advises isolating plastics that are sticky, oozing, crumbling, or acidic-smelling from other objects and seeking conservation advice.
Do not sniff an object closely. Note odors that are apparent during normal handling, improve ventilation, minimize handling, and separate suspect pieces with inert barriers or containers while obtaining professional guidance.
Better language for uncertain objects
Use terms that preserve what you actually know:
- “cream-colored carved face on bamboo back; face material unconfirmed”
- “one-piece molded tile, translucent amber tone; polymer unconfirmed”
- “laminated tile with visible mechanical join”
This is not evasive. It makes the record useful to the next researcher.