World Classic Doppelgängers

I had taken that with a grain of salt as well. I know that there are barns of varying colours, but isn't red predominant?

Great Britain, 1912-13 10d; which is the "evil" twin, but that one not that "evil" really...

I had a tough time finding those two.

Turquoise-blue on the left, greenish blue on the right. The exact shade is too much guesswork from a scan.

It may be a bit more greenish due to the effects of past gum; an overall, yellowish toning, yet slight...

The one on the right is the doppelgänger, but stands on its own merit.

Turquoise-Blue and Deep Turquoise-Blue

Block Cypher, Turquoise-Blue and Deep Dull Greenish Blue

You keep posting 1912. This stamp was not issued until 1 August 1913, and that was a printing by Somerset House with control C.13, i.e., printed towards or during the second half of 2013..

My 2009 SG GB Concise gives only two colours for the 10d; deep turquoise blue for 1912, and turquoise-blue for 1913. It does mention the SH controls, but do not appear differently; same two colours, if SH printed both.

It is the turquoise-blue, at right within my image, not the deep of same, that was released on August 1, 1913. The deep colour was released in 1912.

For those of 1924, the re-prints which I do not collect, block-cypher, turquoise-blue only, and both of those look the same to my eye, although the one on the left looks a bit greener, a little bit.

Guess at the colours...

Great Britain, 1912-13 5d...

I believe that I have all three there; maybe I do, maybe I don't.

The stamps were provisionally printed at Somerset House. Only then did Harrison & Sons print them.
There is an uncleared proof dated 7.6.13.

The control C.13 indicates the printing occurred during 2013. The 10d stamps were never printed with controls A.12, B.12, or B.13. There was no printing of this stamp in the accounting year 1912.
The second control used was D 14 (note the lack of a stop after the letter), a Harrison printing. Hence, after the second accounting period for 2013 when the stamps were printed by the IRS, Harrison did not print them until the second accounting period of 2014. The first period had control C 14.

Both the proof and the control show one thing: there has never been a 1912 issue of this value. The plate was not ready before mid-1913. The deep colour, consequently, was not released in 1912. There was no release of this stamp before 1 August 1913; not in a deep turquoise-blue, not in a pale turquoise-blue, not in any other colour.

Stanley Gibbons lists five shades for this watermark:
* Bright turquoise-blue (your righthand stamp looks very bright compared to the lefthand stamp;
* Turquoise blue
* Deep turquoise blue
* Greenish blue
* Pale greenish blue

The point with deep shades is that they are not pale. Even accounting for all types of variations that make it impossible to determine shades from scans seen on screens, it is very obvious the left stamp in your post has not the slightest deepness of colour.

I do not have the 2009 Concise. I have a few others. Whereas the turquoise-blue has the date 8.13, the deep turquoise-blue does not have a date at all. That does not mean it was issued in 1912. The date after the turquoise-blue stamp is the issue date for the value.

The fact that you have two shades does not mean that you must automatically have both shades. Concise is as it says: concise. It does not list all shades, but shade ranges. Even the 'Specialised' does not list all shades. An example is the 1/2d blue-green. This stamp is also recognised by Hendon in a much scarcer bright blue-green variety unlisted by Gibbons. Note above and below I, purposely, write "lists" and do not use the word "exist." More exist that are summarised by the ones listed.

The righthand stamp of the 'Block Cypher' duo was put to sale in 1935. It was a Harrison printing. Most of these 'Block Cypher' stamps were printed by Waterlow between 1924 and 1934. Stanley Gibbons lists
* Turquoise-blue
* Deep greenish blue
* Dull greenish blue
* Deep dull greenish blue.

Again, no 5d issued before 1913 (30 June). Note the mention of the Somerset House B.13 control and no control ?.12. That means the stamps were not printed at Somerset House before 1913. Since the Somerset House printings, if they occurred, always preceded the Harrison printings - they were provisional -, there was no printing before 1913.

Since you cannot issue stamps before they have been printed, they cannot have been issued before 1913.

Used stamps, yikes. In my opinion all bets are off when it comes to color/hues. NSK is showing mint stamps, much more believable.
Don

Where do you see that the 5d and 10d were not issued in 1912 at all? The list starts out with "1912-22", within my 1982 SG BC Part I catalogue; "1912-24" within my 2009 Concise(what's up with that discrepancy?). So, SG really has no idea whatsoever when the 10d deep turquoise-blue was released? Is it just assumed to be in 1913, since the paler one is dated 1913 within the catalogue(s)? For example, these are all dated within the catalogue...

...but the others are not, and we're supposed to guess.

The use of used stamps makes it all the more challenging, fun.

No problems in having fun. My concern is that other folks can differentiate between the fun posts and the factual posts.
Don