[MattyC]

Good topic. I believe there is no "bubble," when it comes to 51B and 52T Mantles. Simply put, these are two of the most widely desired cards in the hobby, and they also both happen to be incredibly hard to find with great eye appeal.

Someone who has managed to get their hands on a really nice eye appealing 52T or 51B Mantle tends to know how special and desirable a card they have, and it tends to be a cherished piece that will only sell in crisis, death, or when exiting the hobby altogether.

By almost anyone's measure, even when including pre-war cards, the 52T Mantle is likely the #2 or #3 card in the hobby (for example, PSA ranks it #2, one spot after the Wagner and one before the Ruth RC).

Also, as collectors who were young boys in the mid 1980's-- when the 52T card was cementing its iconic status-- enter their prime earning years, they are seeking to obtain it. So we are seeing a fresh new wave of buyer join the men in their 50s, 60s, and 70s who desire the card.

I think the 52T Mantle has appeal that goes way beyond the Yankee fan base; it is perhaps the most recognizable card in the hobby, the one even non collectors have seen. It is basically the standard-bearer of cards.

I also think the prices of truly elite eye-appealling 51B and 52T Mantles will continue to surge. If a dead centered, solid blue background PSA 6 #311 shows up, I believe it will sail pass 50k at auction. Essentially, those without one want one, and those with a decent one dream of having a really nice one. Who knows what any mid-grade 51B with perfect centering and no vertical lines would fetch at auction.

The demand for the #311 card in particular is just enormous, end of the day. Between Mantle collectors, HOF player collectors, 52 Topps Set collectors, Top Sportscard collectors, and random collectors in between, it's a card on everyone's list. And if one has it, it's probably the last one they'd sell in an emergency.