Stamping "JAQUES" on Indian repro..could you tell apart?

Interesting, I hadn't really thought about that but it is kind of obvious. A few possibilities suggest themselves:

1. ivory sets were more status symbols? more likely to be put in the metaphorical cupboard and handled gently. UKP5 in 1849 was signifcant money, it would pay for a junior servant for a year. I doubt that that would explain that many sets.
2. ivory is less brittle over time? My understanding is that it tends to split along the grain like wood does, and to yellow, but the survival of ancient ivory combs and things suggests its fairly robust
3. Ivory is more brittle and only the most gently handled sets survived? Surely people would be selling even broken sets and the pieces would continue to get damaged. This really doesn't look to be the case.
4. The ivory sets on the market have seen their price collapse from the absolutely massive prices that they used to command pre-CITES and so have already had repairs done as they have changed hands in the past? Possible, but it was a limited size of market for those.

Early sets, Dieppe, the regence-derived styles, those Chinese puzzle ball sets, have survived in a way that is difficult to imagine if they were made of wood. Maybe ivory is just less prne to breaking.

what does "heirloom" mean in this context?