Lot #124 Canada #454xxi 1c Reddish Brown, Northern Lights and Dogsled Team, 1967-1973 Centennial Issue, A Fine NH Precancelled Warning Strip of 20 From the Left Side of the Pane, LF-fl Paper and Perf. 11.85

A left side warning strip of 20 of the 1c reddish brown Northern Lights and Dogsled team stamp from the 1967-1973 Centennial issue, printed on LF-fl paper, that appears LF bluish white under UV and contains very sparse concentrations of low and medium fluorescent fibres. Perf. 11.85.

Although Unitrade and Harris list both LF-fl paper, in reality there are several variations of this paper type, which differ according to (1) the basic colour under UV, (2) the ambient fluorescence level and (3) the brightness and concentraton of the fluorescent inclusions contained in the paper, as well as any woodpulp fibres, which tend to make paper look less fluorescent than it is.

The 1c sheet stamps printed by CBN were printed in a number of different shades, depending on when the printings were made:

• Plate 1 and 2 printings made between 1967 and 1968 tend to be in shades of violet brown or brown.
• Plate 1 and 2 printings made between 1968 and 1970 tend to be printed in shades of chocolate and reddish chocolate.
• Plate 3 and 4 printings made between 1970 and 1971 tend to be printed in shades of deep brown, chocolate or reddish chocolate.
• Plate 5 printings made between 1971 and 1973 tend to be printed in shades of reddish brown, though chocolate shades are also found.

The collage shows the differences between some of these shades, though they are easier to see in the flesh for some reason.

The gum used on all printings to 1971 is dextrine, but within this category, there are a number of different types, which differ by the way the gum appears, when viewed in light:

• Early printings have yellowish gum that appears either completely smooth, mildly streaky, or very streaky, and has a semi-gloss sheen.
• Later printings made toward 1970 have gum that has a distinct satin sheen, and can occasionally appear grainy.
• Plate 3 and 4 printings made between 1970 and 1971 often have a gum that appears mottled and "sponged on". This is a very distinct look that is not seen on the earlier plate 1 and 2 printings. However, the normal smooth and streaky versions of the dextrine gum is also found on these printings as well.

The PVA gum used on the plate 5 printings, shows very little variation, but a subtle difference can be found in the sheen and thickness of the gum, with the earlier printings having a thicker gum with a satin sheen, compared to a slightly thinner gum that has an eggshell sheen.

Unitrade values this strip at $25 for very fine. So, a fine centred strip is valued at half this amount, of $12.50. The strip offered here grades 70