I'm not sure what to make of the "Blue Ink" either. And I own one. Using a microscope, I was at least able to determine that the blue color matches the Piedmont blue exactly (At least on mine). I've only seen blurry pictures of the Walsh and I haven't seen this Elberfeld Washington in person when it was being passed around during a show I believe last year. But everyone was in agreement that it wasn't black ink. I'm just curious if it's graded as a "Blue Ink" card or if it's just graded only. I believe that was the issue during the first attempt to sell this card at auction, was getting a TPG to confirm the "Blue" ink. That's why I never bothered to get mine graded. I know it's an authentic problem free card. I don't need a TPG to tell me that. If my card was to go on consignment, then I understand the need for a TPG opinion. But if the TPG doesn't put in the extra effort of matching up the color and confirming the matching print runs of these three cards, then I just don't feel they are doing as much as they could to determine what these cards actually are. I spent a lot of time comparing my card with other T206's and even other sets during that same time period that would have been printed by the same printer. Mine is a Piedmont match. But when I pulled out my over 4000 T59's and started noticing all the color variations of just blue, it was a bit overwhelming but obviously none rare because of the large quantities of each of the color variations.
I forgot to add, I still haven't gotten around to searching all my other Print Group One Old Mills for any other "Blue Ink" variations. So who knows, there might be a fourth one.

__________________
Ron - Uncle Nacki
T206 Master Monster Front/Back Set Collector - www.youtube.com/unclenacki
T206 Basic "The Monster" Set
514/524
T206 Advanced "Master Monster" Front/Back Set
??
??/5258
COMPLETE T206 BACK SUBSETS
Old Mill Southern Leagues - Black Ink
48/48
Sweet Caporal 350-460 Factory 30 Full Color "No Prints"
28/28
NEAR COMPLETE T206 BACK SUBSETS
Polar Bear
245/250
Sovereign 460
50/52
Sweet Caporal 150 Factory 649 Overprint
31/34
Piedmont 350 "Elite 11"
9/11