I sent off this stamp block to get certified and they didn't completely clarify the Scott # for me. I'm posting the cert letter and a picture of the stamp.
Scott catalogue separates color as:
537 - Violet
537a - Deep Red Violet
537b - Light Reddish Violet
537c - Red Violet
I've looked at so many online images. Mine is definitely lighter than 537. And appears to be similar to some 537b, but I know that cameras can't tell me the absolute truth. Any idea why the certifier wouldn't have put the stamp into one of these 4 classes specifically, rather than taking the middle road between 537 and 537b? Are there other hues than what Scott lists? That seems hard to believe since Scott has been doing this for so long, I'm confident that the Scott personnel have seen every version of the stamp.
I look forward to your comments.