R15 - Corner Image Missing

Just received this collection of older US back of book stuff won on ebay last weekend. Looking through I noticed something I think curious about this revenue stamp.
Pretty sure it's a R15 (you experts can set me straight). Here it is on the right, next to another I already had, for comparison. Seems the image of the scroll work on the lower left corner is missing. You can see a faint outline. The surface of the paper is not disturbed.
So what have I got here? A case of poor inking?



I happen to have a copy of Scotts Specialized out of the library, and it makes no mention of any such thing.
Interestingly, last year I put another one of these into this catalogue, sort of a gift for who ever finds it. Looking this one up, my gift popped out at me. Guess I'll keep it.

More likely an EFO than a variety assuming it is not a surface scuff. Neat item though. BTW, the stamp on the right appears to be an R15d (silk paper), based on the blue thread at lower left.

That's pretty neat James! Good eye.

I've read other discussions on the differences between 'variety' and 'EFO', but perhaps this would be a good teaching moment?

I defer to the more experienced collectors to offer a textbook definition of the two ...

Meanwhile, my observations are as such: The impression on this stamp is quite strong in some areas (look at Washington's lapel) and weak, if not missing, in other areas. I would surmise that this could have been caused by one of two things. One, a dry printing (low on ink) or two, a weak pressing (I know there's a term for this, but I don't recall what it is). I think it's the latter.

I think it's a great EFO, James, and should be highlighted as such in your collection. I don't know what kind of premiums classic US revenue EFOs bring, but if this were postage, it would be significant.

Grats!

Brian

I don't know how others would distinguish between EFO and "variety", but here is the way I differentiate them:

An EFO (error, freak, or oddity) is a fairly unique item that does not occur with any type of regularity, e.g., an ink smudge, a preprint paper fold, a perforated pair imperf between, color missing error, etc.

A "variety" on the other hand, occurs with predictable reliability, e.g., engraving anomalies that occur at specific plate positions, double transfers, etc. Even if the occurrence is on only one plate position out of 50, 100, or more, it still occurs with some regularity and is not the result of a single incident, like the above.

For example the C3a inverted jenny is an error, but the 2c red Washingons with cap on one or both 2s are varieties.

Great to see this thread pop up again! Thanks for the responses, all. The consensus seems to be EFO. There is no surface scuffing on the stamp, just a faint outline where the image should be.
Revenuecollector, have you seen one like this before? I know you are familiar with this stamp.

Not this exact anomaly (but if it is a true EFO, there wouldn't be another one *exactly* the same).

I'm not the best person to ask though. While I do collect plate varieties and the occasional extreme EFO, minor ones like this I tend to pass by.

(No offense is intended; one simply cannot collect everything.)

P.S. As long as we are on the subject of EFOs, beware of any dealer trying to charge a premium for revenues with freak perforations. At one time they were indeed sought after, but the general consensus now is that these were manufactured after the fact by some enterprising individual(s). I view them the same as punch or herringbone cancels: defects worthy of hefty discounts.