I bet he'd pick up the diamond trend if that was in his survey!
I got married a few years back, both of us in our mid 30s. I never intended to buy a diamond, and instead bought a sapphire engagement ring. Interestingly, it wasn't until AFTER we got engaged that I found out/realized that both her mother AND grandmother wore sapphire rings. Her 100 year old grandmother had been married multiple times, but her last and favorite engagement ring was a sapphire, despite having certainly received plenty of diamonds throughout her lifetime.