Frank Isbell retired from MLB Oct 3, 1909. So, that explains why his pop report numbers are low. American Lithograph most likely stopped issuing his
cards earlier than the other 150 Series guys.
Lefty Leifield pitched for Pittsburgh till May 1912, so I have no explanation for why his SOVEREIGN 150 cards are tougher to find.
Whatever, if these extravagant prices continue for T206 SOVEREIGN cards, I may be tempted to sell my entire SOVEREIGN complete set of 408 cards.
It would be one of the best investments that I have ever made in Sportscards.
TED Z
T206 Reference
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